Anti-Glioma Effects of Ligustilide or n-Butylphthalide on Their Own and the Synergistic Effects with Temozolomide via PI3K/Akt Signaling Pathway.

Background: Ligustilide (LIG) and n-butylphthalide (NBP) have neuroprotective effects in cerebral ischemia; however, their roles in gliomas are not well-known.This study aimed to explore the anti-glioma effects of LIG and NBP individually and the synergistic effects of temozolomide (TMZ) via the PI3K/Akt Signaling Pathway. Materials and Methods: Cytotoxicity of LIG and NBP alone and in combination with TMZ in U251 cells was determined using the CCk-8. The effect of compounds alone or in combination on cell migration was detected using the wound healing assay, and the invasion was evaluated by transwell assays, respectively. Cell apoptosis was quantified by flow cytometry and the changed expressions of proteins were detected by Western blotting. Results: The results showed that LIG and NBP significantly inhibited the growth of U251 cells at concentrations of 4-10 µg/mL and 1.5-6 µg/mL in a dose-dependent manner (p<0.05, p<0.01). The combination of 20 µg/mL TMZ with LIG in the concentration range of 4-10 µg/mL or with NBP of 0.5-6 µg/mlachieved synergistic effect towardsU251 cells. LIG and NBP, alone or in combination with TMZ, markedly inhibited cell invasion (p< 0.001) and enhanced apoptosis (p< 0.05). The combination of TMZ with LIG or NBP markedly inhibited cell migration (p< 0.001). Western blot analysis showed that LIG, NBP, and TMZ, alone and in combination, significantly decreased the expression of Bcl-2, p-PI3K, and p-Akt, and increased the expression of Bax. Conclusion: Both LIG and NBP exert anti-glioma effects on their own through the PI3K/Akt pathway and enhance TMZ-mediated anti-glioma efficiency via the same pathway.

Natural Products as Anticancer Agents: Current Status and Future Perspectives.

Natural products have been an invaluable and useful source of anticancer agents over the years. Several compounds have been synthesized from natural products by modifying their structures or by using naturally occurring compounds as building blocks in the synthesis of these compounds for various purposes in different fields, such as biology, medicine, and engineering. Multiple modern and costly treatments have been applied to combat cancer and limit its lethality, but the results are not significantly refreshing. Natural products, which are a significant source of new therapeutic drugs, are currently being investigated as potential cytotoxic agents and have shown a positive trend in preclinical research and have prompted numerous innovative strategies in order to combat cancer and expedite the clinical research. Natural products are becoming increasingly important for drug discovery due to their high molecular diversity and novel biofunctionality. Furthermore, natural products can provide superior efficacy and safety due to their unique molecular properties. The objective of the current review is to provide an overview of the emergence of natural products for the treatment and prevention of cancer, such as chemosensitizers, immunotherapeutics, combinatorial therapies with other anticancer drugs, novel formulations of natural products, and the molecular mechanisms underlying their anticancer properties.

Essential oil of Ligusticum chuanxiong Hort. Regulated P-gp protein and tight junction protein to change pharmacokinetic parameters of temozolomide in blood, brain and tumor.

ETHNOPHARMACOLOGICAL RELEVANCE: The existence of the blood-brain barrier/blood tumor barrier (BBB/BTB) severely restricts the effectiveness of anti-tumor drugs, thus glioma is still an incurable disease with a high fatality rate. Chuanxiong (Ligusticum chuanxiong Hort., Umbelliferae) was used as a messenger drug to increase the distribution of drugs in brain tissue, and its application in Chinese herbal formula for treating glioma was also the highest. AIM OF THE STUDY: Our previous researches showed that essential oil (EO) of chuanxiong could promote temozolomide (TMZ) entry into glioma cells in vitro and enhance TMZ-induced anticancer efficiency in vivo, and therefore, the aim of this study was to investigate whether EO could increase the concentration accumulation of TMZ in brain or tumor of C6 glioma rats and the related mechanisms. MATERIALS AND METHODS: The pharmacokinetics were conducted in C6 glioma rats by administering either TMZ alone or combined with EO through oral routes. TMZ concentration in blood, brain and tumor was detected using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) and then pharmacokinetic parameters were calculated. The changed expressions of P-gp protein, tight junction occludin, claudin-5 and zonula occludens-1 (ZO-1) in brain of glioma rats were studied by Western blot to clarify the mechanism. Finally, the chemical composition of EO was analyzed by gas chromatography-massspectrometry (GC-MS). RESULTS: The results showed that EO significantly affected the pharmacokinetic parameters such as Tmax, Cmax and CL (p < 0.01), but did not significantly change the AUC(0→∞) of TMZ in blood (p > 0.05). However, EO markedly improved the AUC(0→∞)of TMZ in brain and tumor (p < 0.01). The calculate drug targeting index was greater than 1, indicating that EO could promote the distribution of TMZ to the brain and tumor. Western blot analysis showed that EO significantly inhibited the expression of P-gp, tight junction protein claudin-5, occludin and ZO-1. And meanwhile, the expressions of P-gp, claudin-5 and occludin also markedly down-regulated in EO-TMZ co-administration treatment. GC-MS analysis of the TIC component of EO was (E)-Ligustilide (36.93%), Terpinolene (7.245%), gamma-terpinene (7.225%) etc. CONCLUSION: EO could promote the distribution of TMZ in the brain and tumor of C6 glioma rats, which may attribute to down-regulate the expression of P-gp, claudin-5 and occludin.

Preparation, in vitro and in vivo Evaluation of Thermosensitive in situ Gel Loaded with Ibuprofen-Solid Lipid Nanoparticles for Rectal Delivery.

Background: Ibuprofen (IBU), a nonsteroidal anti-inflammatory drug, shows poor gastrointestinal absorption due to its low solubility, which limits its clinical application. Objective: In the present study, we aimed to develop thermosensitive gel-mediated ibuprofen-solid lipid nanoparticles (IBU-SLN-ISG) to improve the dissolution and bioavailability of IBU after rectal delivery. Methods: IBU-loaded SLNs (IBU-SLNs) were developed and optimized applying Box-Behnken design. The optimized IBU-SLNs were characterized by physicochemical parameters and morphology. Then, the optimized IBU-SLNs was incorporated into the gel and characterized for gel properties and rheology and investigated its release in vitro, pharmacokinetics in vivo, rectal irritation and rectal retention time. Results: The optimized SLNs had an EE of 90.74 ± 1.40%, DL of 11.36 ± 1.20%, MPS of 166.77 ± 2.26 nm, PDI of 0.27 ± 0.08, and ZP of -21.00 ± 0.59 mV. The FTIR spectra confirmed successful encapsulation of the drug inside the nanoparticle as only peaks responsible for the lipid could be identified. This corroborated well with XRD spectra, which showed a completely amorphous state of the IBU-SLNs as compared to the crystalline nature of the pure drug. The gelation temperature of the prepared IBU-SLN-ISG was 33.30 ± 0.78°C, the gelation time was 14.67 ± 2.52 s, the gel strength was 54.00 ± 1.41 s, and the mucoadhesion was (11.54±0.37) × 102dyne/cm2. The in vitro results of IBU-SLNs and IBU-SLN-ISG showed a biphasic release pattern with initial burst release followed by sustained release. More importantly, IBU-SLN-ISG produced much better absorption of IBU and improved bioavailability in rats. In addition, IBU-SLN-ISG caused no irritation or damage to rectal tissues, and could be retained in the rectum for a long time. Conclusion: Thermosensitive in situ gel loaded with IBU-solid lipid nanoparticles might be further developed as a more convenient and effective rectal dosage form.

Pharmacokinetics of five phthalides in volatile oil of Ligusticum sinense Oliv.cv. Chaxiong, and comparison study on physicochemistry and pharmacokinetics after being formulated into solid dispersion and inclusion compound.

BACKGROUNDS: The dried rhizome of Ligusticum sinense Oliv.cv. Chaxiong has been used to treat cardiovascular and cerebrovascular diseases, atherosclerosis, anemia and stroke. A high purity extract from chaxiong (VOC, brownish yellow oil) was extracted and separated. Its main components were senkyunolide A (SA, 33.81%), N-butylphthalide (NBP, 1.38%), Neocnidilide (NOL, 16.53%), Z-ligustilide (ZL, 38.36%), and butenyl phthalide (BP, 2.48%), respectively. Little is known about the pharmacokinetics of these phthalides in Chaxiong, and different preparations to improve the physicochemistry and pharmacokinetics of VOC have not been investigated. METHODS: At different predetermined time points after oral administration or intravenous administration, the concentrations of SA, NBP, NOL, ZL and BP in the rat plasma were determined using LC-MS/MS, and the main PK parameters were investigated. VOC-P188 solid dispersion and VOC-ß-CD inclusion compound were prepared by melting solvent method and grinding method, respectively. Moreover, the physicochemical properties, dissolution and pharmacokinetics of VOC-P188 solid dispersion and VOC-ß-CD inclusion compound in rats were assessed in comparison to VOC. RESULTS: The absorptions of SA, NBP, NOL, ZL and BP in VOC were rapid after oral administration, and the absolute bioavailability was less than 25%. After the two preparations were prepared, dissolution rate was improved at pH 5.8 phosphate buffer solution. Comparing VOC and physical mixture with the solid dispersion and inclusion compound, it was observed differences occurred in the chemical composition, thermal stability, and morphology. Both VOC-P188 solid dispersion and VOC-ß-CD inclusion compound had a significantly higher AUC and longer MRT in comparison with VOC. CONCLUSION: SA, NBP, NOL, ZL and BP in VOC from chaxiong possessed poor absolute oral bioavailability. Both VOC-P188 solid dispersion and VOC-ß-CD inclusion compound could be prospective means for improving oral bioavailability of SA, NBP, NOL, ZL and BP in VOC.

Sedative and hypnotic effects of Perilla frutescens essential oil through GABAergic system pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine believes that depression syndrome has become one of the core pathogenesis of insomnia. The pharmacology of traditional Chinese medicine points out that Perilla frutescens has the effect of regulating Qi and relieving depression, promoting Qi circulation to relieve pain, so Perilla frutescens may have the potential therapeutic effect on insomnia. Related studies have reported the sedative and hypnotic effects of Perilla frutescens, but these studies have not yet explored the mechanism of sedative and hypnotic effects of Perilla frutescens essential oil (PFEO) through inhalation administration. AIM OF THE STUDY: The purpose of this study is to explore the underlying sedative and hypnotic mechanisms of PFEO through the GABAergic system pathways. MATERIALS AND METHODS: Established the PCPA insomnia model of mice, The open field test, pentobarbital-induced falling asleep rate, latency of sleeping time, and duration of sleeping time experiments were used to evaluate the behavior of mice, the enzyme-linked immunosorbent assay was used to analyze the content of 5-HT and GABA in hypothalamus and cerebral cortex. Immunohistochemical experiment, Western blot experiment and RT-PCR experiment were used to study the mechanism of PFEO through GABAergic pathway to regulate insomnia. The main volatile constituents of PFEO were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: The inhalation of PFEO has sedative and hypnotic effects, which reduce significantly the autonomic activity of PCPA insomnia mice, increase falling asleep rate, shorten latency of sleeping time, and prolong duration of sleeping time; the results of enzyme-linked immunosorbent assay show that PFEO increase the content of 5-HT and GABA in hypothalamus and cerebral cortex. The results showed that inhalation of PFEO increase the expression of GABAAα1 and GABAAα2 positive cells, increase the level of GABAAα1 and GABAAα2 protein and also increase the level of GABAAα1 mRNA and GABAAα2 mRNA in the hypothalamus and cerebral cortex. The highest content of PFEO is Perillaldehyde (54.37%), followed by 1,4-Cineole (7.42%), Acetaldehyde diethyl acetal (6.61%), D-Limonene (5.09%), Eucalyptol (4.94%), etc. CONCLUSION: The inhalation of PFEO has sedative and hypnotic effects, it is speculated that the mechanism of which may be the sedative and hypnotic effects through the GABAergic pathway.

Nose-to-Brain Delivery by Nanosuspensions-Based in situ Gel for Breviscapine.

PURPOSE: Nose-to-brain drug delivery is an effective approach for poorly soluble drugs to bypass the blood-brain barrier. A new drug intranasal delivery system, a nanosuspension-based in situ gel, was developed and evaluated to improve the solubility and bioavailability of the drug and to prolong its retention time in the nasal cavity. MATERIALS AND METHODS: Breviscapine (BRE) was chosen as the model drug. BRE nanosuspensions (BRE-NS) were converted into BRE nanosuspension powders (BRE-NP). A BRE nanosuspension in situ gelling system (BRE-NG) was prepared by mixing BRE-NP and 0.5% gellan gum (m/v). First, the BRE-NP were evaluated in terms of particle size and by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Subsequently, the critical ionic concentration of the gellan gum phase transition, influence of the deacetylated gellan gum (DGG) concentration on the expansion coefficient (S%), water-holding capacity, rheological properties and in vitro release behaviour of the BRE-NG were investigated. The pharmacokinetics and brain distribution of the BRE-NG after intranasal administration were compared with those of the intravenously injected BRE-NP nanosuspensions in rats. RESULTS: The rheology results demonstrated that BRE-NG was a non-Newtonian fluid with good spreadability and bioadhesion performance. Moreover, the absolute bioavailability estimated for BRE-NG after intranasal administration was 57.12%. The drug targeting efficiency (DTE%) of BRE in the cerebrum, cerebellum and olfactory bulb was 4006, 999 and 3290, respectively. The nose-to-brain direct transport percentage (DTP%) of the cerebrum, cerebellum and olfactory bulb was 0.975, 0.950 and 0.970, respectively. CONCLUSION: It was concluded that the in situ gel significantly increased the drug retention time at the administration site. Therefore, the nanosuspension-based in situ gel could be a convenient and effective intranasal formulation for the administration of BRE.

Sedative and hypnotic effects of compound Anshen essential oil inhalation for insomnia.

BACKGROUNDS: The chemical composition of many essential oils indicates that they have sedative and hypnotic effects, but there is still a lack of systematic studies on the sedative and hypnotic effects of essential oils. In addition, aromatherapy does not seem to have the side effects of many traditional psychotropic substances, which is clearly worthwhile for further clinical and scientific research. The clinical application of essential oils in aromatherapy has received increasing attention, and detailed studies on the pharmacological activities of inhaled essential oils are increasingly needed. HYPOTHESIS/PURPOSE: As insomniacs are usually accompanied by symptoms of depression and anxiety of varying degrees, based on the theory of aromatherapy of Traditional Chinese Medicine, this experiment is to study a Compound Anshen essential oil that is compatible with Lavender essential oil, Sweet Orange essential oil, Sandalwood essential oil and other aromatic medicine essential oils with sedative and hypnotic effects, anti-anxiety and anti-depression effects. To study the sedative and hypnotic effects of Compound Anshen essential oil inhaled and the main chemical components of Compound Anshen essential oil, and to compare and analyze the pharmacodynamics of diazepam, a commonly used drug for insomnia. METHODS: The Open field test and Pentobarbital-induced sleep latency and sleep time experiments were used to analyze and compare the sedative and hypnotic effects of inhaling Compound Anshen essential oil and the administration of diazepam on mice. The changes of 5-HT and GABA in mouse brain were analyzed by Elisa. The main volatile constituents of Compound Anshen essential oil were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: Inhalation of Compound Anshen essential oil can significantly reduce the spontaneous activity of mice, reduce latency of sleeping time and prolong duration of sleeping time. The results of enzyme-linked immunosorbent assay showed that Compound Anshen essential oil can increase the content of 5-HT and GABA in mouse brain. The main volatile chemical constituents of the Compound Anshen essential oil are D-limonene (24.07%), Linalool (21.98%), Linalyl acetate (15.37%), α-Pinene (5.39%), and α-Santalol (4.8%). CONCLUSION: The study found that the inhalation of Compound Anshen essential oil has sedative and hypnotic effect. This study provides a theoretical basis for further research and development of the sedative and hypnotic effects of Compound Anshen essential oil based on the theory of aromatherapy.

The influence and mechanism of ligustilide, senkyunolide I, and senkyunolide A on echinacoside transport through MDCK-MDR1 cells as blood-brain barrier in vitro model.

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 â†’ B direction by ethylenediaminetetraacetic acid-Na2 suggested that ECH was absorbed via the paracellular route. The transport of ECH in A â†’ 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.

Panax Notoginseng Saponins as a Novel Nature Stabilizer for Poorly Soluble Drug Nanocrystals: A Case Study with Baicalein.

This study is aimed at seeking a nature saponin-based stabilizer for drug nanosuspensions. A poorly soluble drug (baicalein, BCL) was used as a model drug. BCL nanosuspensions with particle size of 156 nm were prepared by means of homogenization and converted into BCL nanocrystals (BCL-NC) stabilized with panax notoginseng saponins (PNS). It was found that PNS was able to prevent the aggregation of BCL-NS during storage and improve the redispersibility of BCL-NC after freeze-drying and spray-drying, compared with polymer stabilizer PVPK30. The freeze-dried and spray-dried BCL-NC with PNS exhibited excellent performance as evidenced by scanning_electron_microscope (SEM) analysis. It was the reason that PNS possessed the interfacial property (41.69 ± 0.32 mN/m) and electrostatic effect (-40.1 ± 1.6 mV), which could easily adsorb onto the surface of hydrophobic BCL nanocrystals and prevent from its aggregation. It is concluded that PNS can be used as an effective nature stabilizer for production of drug nanocrystals.

Pharmacokinetic comparative study of gastrodin after oral administration of Gastrodia elata Bl. extract and its compatibility with the different indigents of Ligusticum chuanxiong Hort. to rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Da Chuan Xiong Decoction Compound preparation (DCXDCP) is a classic TCM formula of an aqueous extract made from Chuanxiong Rhizoma (Ligusticum chuanxiong Hort., umbelliferae) and Tianma Rhizoma (Gastrodia elata Bl., Orchidaceae). Gastrodin (GAS), a bioactive component of tianma, its pharmacokinetic (PK) behavior significantly changed after oral administration of DCXDCP compared with the extract of tianma. However, little is known about how the ingredients of chuanxiong influenced on the PK of GAS. AIM OF THE STUDY: To study the possible PK behavior differences of GAS after individually oral administration of tianma extract and tianma extract mixed with different active ingredients of chuanxiong to rats, as well as explore whether there were some herb-herb interactions. MATERIALS AND METHODS: Different DCXDCP suspensions were prepared by mixing tianma extract with different active ingredients of chuanxiong. The rats were randomly assigned to six groups and were orally treated with different DCXDCP. At different predetermined time points after administration, the concentrations of GAS in the rat plasma were determined using HPLC, and the main PK parameters were investigated. RESULTS: The results showed that tetramethylpyrazine had no significant effects on the PK parameters of GAS (p>0.05), whereas ferulic acid (FA), total phenolic acids and total alkaloids significantly increased AUC0-∞ (p<0.05). In general the observed changes in the PK parameters of GAS in DCXDCP could be closely related to the total phenolic acids and total alkaloids. CONCLUSION: It could be shown that total phenolic acids and total alkaloids present in Ligusticum chuanxiong in addition to other components not tested yet play an important role in affecting the PK of gastrodin in DCXDCP.

Elucidation of Transport Mechanism of Paeoniflorin and the Influence of Ligustilide, Senkyunolide I and Senkyunolide A on Paeoniflorin Transport through Mdck-Mdr1 Cells as Blood-Brain Barrier in Vitro Model.

The objectives of the present investigation were to: (1) elucidate the transport mechanism of paeoniflorin (PF) across MDCK-MDR1 monolayers; and (2) evaluate the effect of ligustilide (LIG), senkyunolide I (SENI) and senkyunolide A (SENA) on the transport of PF through blood-brain barrier so as to explore the enhancement mechanism. Transport studies of PF were performed in both directions, from apical to basolateral side (A→B) and from basolateral to apical sides (B→A). Drug concentrations were analyzed by LC-MS/MS. PF showed relatively poor absorption in MDCK-MDR1 cells, apparent permeability coefficients (Papp) ranging from 0.587 × 10(-6) to 0.705 × 10(-6) cm/s. In vitro experiments showed that the transport of PF in both directions was concentration dependent and not saturable. The B→A/A→B permeability ER of PF was more than 2 in the MDCK-MDR1 cells, which indicated that the transport mechanism of PF might be passive diffusion as the dominating process with the active transportation mediated mechanism involved. The increased Papp of PF in A→B direction by EDTA-Na2 suggested that PF was absorbed via the paracellular route. The P-gp inhibitor verapamil could significantly increase the transport of PF in A→B direction, and ER decreased from 2.210 to 0.690, which indicated that PF was P-gp substance. The transport of PF in A→B direction significantly increased when co-administrated with increasing concentrations of LIG, SENI and SENA. An increased cellular accumulation of Rho 123 and Western blot analysis indicated that LIG, SENI and SENA had increased the transport of PF in the BBB models attribute to down-regulate P-gp expression. A decrease in transepithelial electrical resistance (TEER) during the permeation experiment can be explained by the modulation and opening of the tight junctions caused by the permeation enhancer LIG, SENI and SENA.

Microcrystalline cellulose-carboxymethyl cellulose sodium as an effective dispersant for drug nanocrystals: A case study.

This study is aimed at seeking an alternative dispersant for spray drying of drug nanosuspensions. The ideal dispersant is not only able to prevent the agglomeration of drug nanocrystals in the suspension state, but also it is able to preserve redispersibility of drug nanocrystals after drying. An active pharmaceutical ingredient (API) was used as a model drug. API nanosuspensions were prepared by homogenization and converted into nanocrystals powder (API-NP) with microcrystalline cellulose-carboxymethyl cellulose sodium (MCCS) via spray drying. It was found that MCCS was able to prevent the aggregation of API-NP in the suspension state and the agglomeration during spray-drying process, possibility due to its high Zeta potential and steric barrier from network structure, and reduction of API size at nanoscale and incorporation into MCCS network structure did not affect the solid state of API as evidenced by DSC and XRD analysis. The spray-dried API-NP/MCCS powders exhibited excellent sphere-shape performance, and could easily redispersed to API-NC suspensions state. Dissolution of the spray-dried API-NP was distinctly superior to those of the crude powder and physical mixture, respectively. Within 30 min, approximate 85.87% of API was dissolved from the API-NP/MCCS. MCCS was demonstrated to be an effective dispersant for spray-dried drug nanocrystals and preservation of the nanocrystals associated with excellent redispersibility.

The Roles of Vitrification of Stabilizers/Matrix Formers for the Redispersibility of Drug Nanocrystals After Solidification: a Case Study.

To elucidate the roles of vitrification of stabilizers/matrix formers for the redispersibility of drug nanocrystal powder after solidification at storage stress, the influence of different drying methods and storage stresses on stability of drug nanocrystals was systemically investigated. A poorly soluble drug, baicalin, used as model drug was converted into baicalin nanocrystals (BCN-NC). The residual moisture contents of BCN-NC were applied at two different stress conditions defined as "conservative" (<1%) and "aggressive" (>1%), respectively. The influence of different stabilizers, matrix formers, and storage stresses on the redispersibility of BCN-NC powder was systemically investigated, respectively. The results showed that storage stresses had significantly influence the redispersibility of BCN-NC. Aggressive storage temperature and residual moisture could be unfavorable factors for stability of drug nanocrystals, due to the exacerbation of aggregation of BCN-NC induced by vitrification. It was demonstrated that vitrification of spray-dried BCN-NC was dependent on temperature and time. The polymeric stabilizers hydroxypropylmethylcellulose (HPMC) and sodium carboxymethyl starch (CMS-Na) with high glass transition temperature (T g) played more important role in protecting the BCN-NC from breakage during storage, compared to the surfactants Tween 80, D-α-tocopherol acid polyethylene glycol 1000 succinate (TPGS), or RH 40. Besides, the polyvinylpyrrolidone K30 (PVP K30) and lactose with high T g were effective matrix formers for preserving the redispersibility of BCN-NC. It was concluded that the vitrification transition of stabilizers/matrix formers could be responsible for aggregation of drug nanocrystals during storage, which was a time-dependent process. The suitable residual moisture contents (RMC) and T g were very important for preserving the stability of drug nanocrystals during storage.

Formulations, hemolytic and pharmacokinetic studies on saikosaponin a and saikosaponin d compound liposomes.

The aim of this study was to develop and optimise a saikosaponin a and saikosaponin d compound liposome (SSa-SSd-Lip) formulation with reduced hemolysis and enhanced bioavailability. A screening experiment was done with Plackett-Burman design, and response surface methodology of five factors (EPC/SSa-SSd ratio, EPC/Chol ratio, water temperature, pH of PBS, and ultrasound time) was employed to optimise the mean diameter, entrapment efficiency of SSa and SSd, and the reduction of hemolysis for SSa-SSd-Lip. Under the optimal process conditions (EPC/SSa-SSd ratio, EPC/Chol ratio, water temperature and pH of PBS were 26.71, 4, 50 °C and 7.4, respectively), the mean diameter, the entrapment efficiency of SSa, the entrapment efficiency of SSd and the hemolysis were 203 nm, 79.87%, 86.19%, 25.16% (SSa/SSd 12.5 mg/mL), respectively. The pharmacokinetic studies showed that the SSa-SSd-Lip had increased circulation time, decreased Cl, and increased AUC, MRT and T1/2ß (p < 0.05) for both SSa and SSd after intravenous administration in comparison with solution.

[Application characteristics and situation analysis of volatile oils in database of Chinese patent medicine].

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.

A novel high-pressure precipitation tandem homogenization technology for drug nanocrystals production - a case study with ursodeoxycholic acid.

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.

D-Alpha-tocopherol acid polyethylene glycol 1000 succinate, an effective stabilizer during solidification transformation of baicalin nanosuspensions.

Baicalin nanosuspensions, stabilized with 10% TPGS (relative to the weight of baicalin), were transformed into nanosuspensions powders by solidification process. Solidification methods for this transformation included freeze-drying, spray drying or vacuum drying. High pressure homogenization was applied for production of baicalin nanosuspensions used TPGS, SDS, P188, HPMC and MC as stabilizer, respectively. The influence of the different solidification transformation methods on the redispersibility of solid drug nanosuspensions was systemically investigated, such as freeze-drying, spray drying and vacuum drying. Each method was applied with three grades of process stresses called as "conservative", "moderate" and "aggressive" conditions, and the redispersibility index (RDI) of nanosuspensions stabilized by stabilizers (such as TPGS, SDS, P188, HPMC and MC) during those process was investigated. The results showed that there was significant difference in RDI of nanosuspensions after solidification process. The RDI(a) (1.09, 1.01, 1.05, 0.99), RDI(b) (1.03, 0.99, 1.06, 1.02) and RDI(c) (1.01, 1.01, 1.09, 1.08) of nanosuspensions stabilized by TPGS were more small during different solidification process, compared with those of nanosuspensions stabilized by other stabilizer. It was concluded that the baicalin nanosuspensions were subjected to agglomeration or crystal growth during solidification transformation, especially at high aggressive stress conditions. Meanwhile, compared to other stabilizer, the TPGS was more effective for stability of baicalin nanosuspensions, which could exhibit higher affinity to the drug crystal and stronger surface adsorption at different solidification stresses.

[Advance in studies on establishment methods of responsive drug delivery system].

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.

[Study on effect of combined application on distribution of gastrodigenin in rats].

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.