Showing papers in "Acta pharmaceutica Sinica in 2005"

[Isolation, purification and structural analysis of a polysaccharide MDG-1 from Ophiopogon japonicus].

Abstract: Aim To separate and purify the anti-myocardial ischemic polysaccharide fraction with a homogenous molecular weight from Ophiopogon japonicus, then study the chemical structure of the parts. Methods Crude polysaccharides were prepared by extracting the tube root fraction of Ophiopogon japonicus with water, then precipitation with ethanol. From the crude polysaccharides, the polysaccharide of MDG-1 was separated and purified using ultrafiltration, DEAE Sepharose FF and Sephadex G-25 column chromatography. Its structure was studied by complete hydrolysis, periodate oxidation, Smith degradation, methylation analysis, 1H NMR and 13C NMR analysis etc. Results and conclusion MDG-1 was a water-soluble beta-D-fructosan, containing a backbone composed of Fruf (2 --> 1), and a branch of Fruf (2 --> 6) Fruf (2 --> per average 2. 8 of main chain residues. Mn, Mw and Mp of MDG-1 were 3 400, 4 800 and 5 000, respectively. MDG-1 contains trace of Glc, which maybe connect to its reducing terminal. Molar ratio of Fru and Glc is approximately 35: 1.

[Vitexicarpin, a flavonoid from Vitex trifolia L., induces apoptosis in K562 cells via mitochondria-controlled apoptotic pathway].

Abstract: Aim To investigate the inhibitory effect of vitexicarpin on the proliferation of human cancer cells and its mechanism of action. Methods The inhibitory effect of vitexicarpin on the proliferation of human cancer cells was evaluated by the SRB method and its apoptosis-inducing effect was demonstrated by morphological observation under light microscope, flow cytometric analysis and agarose gel electrophoresis. The proteins related to apoptosis were examined by Western blotting analysis. Results Vitexicarpin significantly inhibited the proliferation of human cancer cells, A2780, HCT-15, HT-1080 and K562, with the IC50 values of (19.1 +/- 2.4) micromol x L(-1) for A2780(48 h), (0.66 +/- 0.10) micromol x L(-1) for HCT-15(48 h), (0.44 +/- 0.06) micromol x L(-1) for HT-1080 (48 h) and (0.28 +/- 0.14) micromol x L(-1) for K562 (24 h). The cells treated with vitexicarpin showed characteristic morphology typical for apoptosis and gave dose-dependent sub-G0/G1 peak in the flow cytometric analysis and DNA ladder on agarose gel electrophoresis. In Western blotting analysis, the cleavage of PARP and caspase-3, the release of cytochrome c from mitochondria into the cytosol, the decrease of Bcl-2 expression level, and the down-regulation of the ratio of Bcl-2/Bax expression level were examined in the K562 cells treated with vitexicarpin. Conclusion Vitexicarpin induces apoptosis in K562 cells via mitochondria-controlled apoptotic pathway.

[Physical-chemical properties and structure elucidation of abPS isolated from the root of Achyranthes bidentata].

Abstract: AIM To study the physicochemical properties and the structure of Achyranthes bidentata polysaccharide (AbPS) METHODS AbPS was isolated from the roots of Achyranthes bidentata Bl, and purified by gel filtration chromatography The distribution of the molecular weight of AbPS was determined by ESI-MS The structure of AbPS was deduced by methylation analysis, reductive-cleavage and 13CNMR spectroscopy RESULTS AbPS was shown to compose of fructose residues and glucose residues and the molar ratio was 8:1 AbPS contain 2,1-linked fructose residue, 2,1-linked fructose residue, 1,2,6-linked fructose residue, terminal fructose residue and terminal glucose residue CONCLUSION AbPS is a fructan and belong to graminan

Genetic diversity and molecular authentication of wild populations of Dendrobium officinale by RAPD

Abstract: AIM Genetic diversity, relationship and molecular authentication of total 8 wild populations of Dendrobium officinale were investigated using RAPD markers. METHODS 10 random decamer primers were screened for Random Amplified Polymophic DNA (RAPD) fragments. A DNA molecular dendrogram was established based on cluster analysis by UPGMA (unweighted pair-group method with arithmetic average), and the relationship of the wild populations were analyzed, and all the wild populations were authenticated. RESULTS A total of 439 loci with an average of 43.9 loci per primer and 54.9 loci per population were amplified from 8 wild populations by 10 effective primers. In the total 104 amplified bands, 95 were polymorphic, corresponding to 91.35% genetic polymorphism. The genetic distances were 0. 590 to 0. 727, with an average of 0. 686. CONCLUSION Distinct genetic differences and extensive genetic diversity were presented among the wild populations. RAPD markers were an informative and useful tool for the genetic diversity, evaluation and authentication of wild populations of Dendrobium officinale. Primer S412 could be used to authenticate 8 wild populations completely.

Protective effect of hydroxysafflor yellow A on experimental cerebral ischemia in rats

Abstract: AIM To investigate the protective effect of hydroxysafflor yellow A (HSYA), a soluble element extracted from Carthamus tinctorius L., on focal cerebral ischemia in rats. METHODS Focal cerebral ischemia in male Wistar-Kyoto (WKY) rats were induced by permanent middle cerebral artery occlusion (MCAO). Three doses of 1.5, 3.0 and 6.0 mg x kg(-1) of HSYA were administrated to three groups of rats, separately, via sublingular vein injection 30 min after the onset of ischemia. 24 h after ischemia in rats, neurological deficit scores were evaluated and the infarction area of brain was assessed by quantitative image analysis. The in vitro neuroprotective effect of HSYA was tested in cultured fetal cortical neurons exposed to glutamate and sodium cyanide (NaCN). RESULTS HSYA at doses of 3.0 and 6.0 mg x kg(-1) exerted significant neuroprotective effects on rats with focal cerebral ischemic injury as expressed by neurological deficit scores and reduced the infarct area as compared with saline group, and the potency of HSYA at dose of 6.0 mg x kg(-1) was similar to that of 0.2 mg x kg(-1) of nimodipine. In vitro studies, HSYA significantly inhibited neurons damage induced by exposure to glutamate and NaCN in cultured fetal cortical cells. CONCLUSION HSYA has potential neuroprotective action against focal cerebral ischemia in rats and cultured rat fetal cortical neurons as well.

Chemical constituents from the seeds of Annona squamosa

Abstract: Aim To study the antitumor active constituents of the seeds from Annona squamosa L. (Annonaceae). Methods Various chromatographic techniques were used to isolate and purify the constituents. Their physico-chemical properties and spectral data were determined to elucidate the structures. Results Eleven compounds were isolated and identified as annonaceous acetogenins: squamocenin (1), annotemoyin-2 (2), reticulatain-2 (3), squamocin-I (4), squamocin-B (5), squamocin (6), motrilin (7), squamostatin-D (8), squamostatin-E (9), cherimolin-1 (10), cherimolin-2 (11) from the ethyl alcohol extract of A. squamosa L. Conclusion Squamocenin (1) is a new acetogenin. Annotemoyin-2 (2) and reticulatain-2 (3) were isolated from this plant for the first time.

Immunopharmacological action of sinomenine, an alkaloid isolated from Sinomenium acutum, and its mechanism of action in treating rheumatoid arthritis

Abstract: Aim To observe the effects of sinomenine on the immune functions and apoptosis of murine lymphocyte as well as on human synovial fibroblast proliferation. Methods Both in vivo and in vitro tests were adopted. The lymphocyte proliferation induced by mitogens was assayed by MTT method. Spleen T lymphocyte subtypes were tested with flow cytometry. Spleen lymphocyte apoptosis was analyzed by flow cytometry and DNA ladder methods. In vitro test was adopted to observe the effects of sinomenine on the proliferation of human fibroblast of rheumatoid arthritis. Results Sinomenine can inhibit the proliferation of mouse lymphocytes induced by ConA, LPS and anti-CD3 mAb but not PMA in vitro, and inhibit the proliferation induced by LPS and PMA in vivo. Sinomenine can reduce up-regulated CD4+/CD8+ ratio of T lymphocyte subtype in adjuvant arthritis rat. At the same concentration increased apoptosis ratio. As to human synovial fibroblast, sinomenine can significantly inhibit proliferation of human fibroblast. Conclusion Sinomenine can inhibit the immunological function and correct imbalance of CD4+/CD8+ ratio of T lymphocyte subtype. It can also increase apoptosis ratio of spleen lymphocyte. This may be the mechanism of its immunological inhibitory effect.

[The tissue distribution in mice and pharmacokinetics in rabbits of oridonin-solid lipid nanoparticles].

Abstract: Aim To investigate the tissue distribution and pharmacokinetics of oridonin-solid lipid nanoparticles in animals. Methods HPLC method was established to determine the concentration of oridonin in serum of rabbits and in different tissues of mice. The results after tail iv administration of oridonin and oridonin solid lipid nanoparticles were compared. Results The relative tissue content of oridonin of solid lipid nanoparticles in the liver, spleen, lung, heart and kidney were 4.25%, 3.44%, 1.19%, 0.52% and 0.60%, respectively. The concentration-time curves of oridonin and oridonin solid lipid nanoparticles were both fitted to the three-compartment model. T(1/2)pi = 0.087 h, T(1/2)alpha = 1.65 h, T(1/2)beta = 32.36 h, V(C) = 0.66 mL.kg(-1). Conclusion Solid lipid nanoparticles could increase the hepatic and lienic targeting efficiency of oridonin in mice and improve its bioavailability. Solid lipid nanoparticles were helpful for oridonin to reach a long circulation time and were hopeful to be its novel drug carrier.

[Chemistry of polysaccharide Lzps-1 from Ganoderma lucidum spore and anti-tumor activity of its total polysaccharides].

Abstract: Aim To study the structure and anti-tumor activity of polysaccharide from Ganoderma lucidum spore treated with microwave Methods DEAE-cellulose and Sephadex G-50 column chromatography were used to isolate and purify the polysaccharide whose structure was characterized by using chemical and spectral methods Results and conclusion One polysaccharide, named Lzps-1 was obtained from the water extract, with its molecular weight estimated by HPGPC to be 8000 Its structure was investigated to be glucan The total polysaccharides, Lzps processed antitumor activity against sarcoma 180 and Lewis lung cancer in mice and enhanced the NK cell activity Lzps-1 is obtained for the first time from Ganoderma spore Lzps has anti-tumor activity

Preparation of silymarin proliposomes and its pharmacokinetics in rats

Abstract: Aim To study the preparation of silymarin proliposomes. To study its physicochemic properties, its pharmacokinetical characteristics and bioavailability in rats after oral administration. Methods Silymarin proliposomes were prepared by film-deposition on carriers. When the proliposomes were contacted with water to form liposome suspensions, the tests of physicochemical properties including encapsulation efficiency, particle size and stability of the formed liposome suspensions were determined by HPLC, laser-particle-sizer and etc. The concentrations of non-conjugated and overall silymarin in plasma of rats and their pharmacokinetic behaviors after oral administration were studied by RP-HPLC. The pharmacokinetic parameters were computed by software program 3P97. Results The encapsulation efficiency of silymarin liposomes could be more than 90%, with an average particle size of about 238.8 nm and a very good stability. The high bioavailability of silymarin proliposomes could be gotten by oral administration. Conclusion Compared with silymarin, silymarin proliposome is a stable and easily industrialized preparation and did enchance the gastrointestinal absorption of silymarin.

Microbiological assay for the determination of azithromycin in ophthalmic solutions.

Abstract: Programa de Pos-Graduacao em Ciencias Farmaceuticas Departamento de Farmacos e Medicamentos UNESP, Rodovia Araraquara-Jau, km 1, Araraquara- SP-CEP 14801-902

Steroidal constituents from Dioscorea parviflora

Abstract: Aim To study the chemical constituents of Dioscorea parviflora. Methods The chemical constituents were isolated by silica gel and RP-18 column chromatography, and their chemical structures were elucidated by IR, NMR and MS. Results Eleven steroides have been isolated from EtOH extract of Dioscorea parviflora and identified as isonarthogenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (I), diosgenin-diglucoside (II), prosapogenin A of dioscin (III), dioscin (IV), deltonin (V), deltoside (VI), methyl deltoside (VII), diosgenin 3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (VIII), parvifloside (IX), methyl parvifloside (X), diosgenin (XI), and a mixture of beta-sitosterol and stigmasterol. Conclusion Compound X is a new compound. Compounds VII and X were methyl ethers of VI and IX, respectively, and may be produced during isolation. Compound I is isolated from Dioscorea L., and II, IV from Dioscorea parviflora for the first time.

Stereoselectivity of skin carboxylesterase metabolism

Abstract: Aim To study the stereoselectivity of skin carboxylesterase metabolism and its molecular biological foundation for improving drug percutaneous absorption Methods Ketoprofen ethyl ester was used as a model drug, and skin homogenate was applied for studying the stereoselectivity of carboxylesterase metabolism Human liver L02 cell was used as control of carboxylesterase expression, and RT-PCR was used for studying the expression of carboxylesterase Results The main metabolite of ketoprofen ethyl ester in human skin homogenate was R-ketoprofen Human carboxylesterase-2 was highly expressed in skin and its cells However, the expression of human carboxylesterase-1 was very weak or not detectable Conclusion Human carboxylesterase-2 is the main hydrolytic enzyme of prodrugs in percutaneous absorption, and shows metabolic stereoselectivity to prodrugs with chiral esters

Studies on chemical constituents of Pinus armandii

Abstract: AIM: To study chemical constituents from pine cone of Pinus armandii Franch METHODS: The constituents were isolated by chromatographic method and the structures were identified on the basis of spectral analysis RESULTS: Four compounds were identified as 7-oxo-12alpha, 13beta-dihydroxyabiet-8(14)-en18-oic acid (I), 7-oxo-13beta-hydroxyabiet-8 (14)-en-18-oic acid (II), 8 (14)-podocarpen-13-on-18-oic acid (III) and lambertianic acid (IV) CONCLUSION: Compound I is a new diterpenoid and compounds II, III were isolated from this plant for the first time

Effect of salidroside on mitochondria injury induced by sodium azide

Abstract: AIM To study the protective effect of salidroside on mitochondria injury induced by sodium azide. METHODS Human neuroblastoma SH-SY5Y cells were exposed to sodium azide with different concentration of salidroside, then cell viability was measured by thiazolyl blue (MTT) method and mitochondrial membrane potential (MMP) was detected by JC-1 method. Protective effect of salidroside against disfunction of mitochondria induced by sodium azide was detected by resazurin method. RESULTS After exposing to 64 mmol x L(-1) sodium azide for 4 hours, cell viability and MMP of SH-SY5Y cells significantly decreased. When pretreated with salidroside, the cell damage was greatly reduced and the mitochondrial membrane potential was maintained. Furthermore, salidroside can protect function of rat brain mitochondria against damage induced by sodium azide. CONCLUSION Salidroside was demonstrated to play an important role in improving the function of mitochondria.

Alkaline-degradation products of ginsenosides from leaves and stems of Panax quinquefolium

Abstract: Aim To study the alkaline-degradation products of ginsenosides from leaves and stems of Panax quinquefolium L. Methods Isolation and purification were carried out on silica gel and HPLC; the structures of chemical constituents were elucidated by spectral analysis. Results From the alkaline-degradation products, nine compounds were identified as: 20 (S) -protopanaxadiol (I), 20 (S) -dammar-25 (26)-ene-3beta, 12beta, 20-triol (II), 24 (R) -ocotillol (III), 20 (S) -protopanaxatriol (IV), 20 (S) -dammar-25 (26)-ene-3beta, 6alpha, 12beta, 20-tetrol (V), dammar-20 (21), 24-diene-3beta, 12beta-diol (VI), dammar-20(21), 24-diene-3beta, 6alpha, 12beta-triol (VII), 20 (S), 24 (S) -dammar-25 (26) -ene-3beta, 6alpha, 12beta, 20, 24-pentanol (VIII), 20 (S) -dammar-23-ene-25-hydroperoxyl-3beta, 6alpha, 12beta, 20-tetrol (IX). Conclusion The configuration of C20 position of ginsenosides was not changed by alkaline-degradation. The complete assignments of 1H and 13C NMR chemical shifts of four new compounds V, VII, VIII, IX, were acquired by means of 2D NMR spectra. Compound I showed antitumor effect on human colon carcinoma cells in vitro.

[Molecular identification of medicinal plants: Dendrobium chrysanthum, Dendrobium fimbriatum and their morphologically allied species by PCR-RFLP analyses].

Abstract: Aim To establish a simple method for molecular identification of original plants of D. chrysanthum and D. fimbriatum using molecular marker rDNA ITS region. Methods Restriction patterns of ITS fragments were obtained using PCR-RFLP method. The PCR products of D. chrysanthum and its morphologically allied species were digested at 37 degrees C by Cla I and Apa LI, those of D. fimbriatum and its morphologically allied species were digested by Sph I. Results D. chrysanthum, D. fimbriatum and their morphologically allied species could be identified by predicted restriction profiles of PCR-RFLP. The botanical origin of twenty-five fresh samples of "Shihu" collected in markets was identified by this method. Conclusion The results showed that PCR-RFLP analysis of the rDNA ITS region is a feasible, simple and inexpensive method for determining the botanical origin of the traditional Chinese medicine "Shihu".

Ginsenoside-Ro enhances cell proliferation and modulates Th1/Th2 cytokines production in murine splenocytes.

Abstract: Aim To study the effects of gindenoside-Ro on cell proliferation and cytokine production in murine splenocytes. Methods The effect of ginsenoside-Ro on murine splenocytes proliferation was studied using [3H] thymidine incorporation assay. Effects of ginsenodide-Ro on the production of cyrokines interleukin-2 (IL-2), interferon-γ(IF-Nγ) and interleukin-4 (IL-4) from mutine splenocytes were detected by ELISA method. Effects of ginsenoside-Ro on mRNA level of TH1 cytokine IFN-γ and Th2 cytokine IL-4 were evaluated by reverse transcription polymerase chain reaction (RT-PCR) analysis. Results Ginsenoside-Ro showed no mitogenic effect on unstimulated murine splenocytes. It enhanced the proliferation of Con A-induced murine splenocytes and the production of IL-2 at concentrations of 1-10 μmol•L^(-1). Moreover, ginsenoside-Ro increased the production and expression of Th2 cytokine IL-4 and decreased the production and expression of Th1 cytokine 1FN-γ in Con A-induced murine splenocytes at concentrations of 2-10μmol•L^(-1). Conclusion Ginsenside-Ro showed immunomodulatory effects by regulating the production and expression of Th1/Th2 cytokines in murine splenocytes.

The biotransformation of kaempferitrin by human intestinal flora

Abstract: Aim To study the biotransformation of kaempferitrin, a major chemical principle of the fruits of Siraitia grosvenori (Swingle) C. Jeffery, with human intestinal flora. Methods The kaempferitrin was incubated with human intestinal flora. The biotransformation products were isolated and purified by chromatographic methods and the structures were determined by spectroscopic techniques. Results Kaempferitrin was converted into kaempferol 3-O-alpha-L-rhamnoside (afzelin, I) , kaempferol 7-O-alpha-L-rhamnoside (II), kaempferol (III) and p-hydroxybenzoic acid (IV) by human intestinal flora. rhamnoside (II), kaempferol (III) and p-hydroxybenzoic acid (IV) by human intestinal flora. Conclusion The structure of kaempferitrin can be biotransformatedly converted by human intestinal flora.

New dimeric phthalide derivative from Angelica sinensis

Abstract: Aim To study the chemical constituents of the roots of Angelica sinensis. Methods Silica gel column chromatography was used to separate the chemical constituents. Their structures were elucidated by chemical and spectral analysis (IR, MS, 1D and 2D NMR, etc.). Results Besides three known phthalide derivatives, one new dimeric phthalide derivative and a pair of epimer were isolated and their structures were identified as Z-3′,8′,3′a,7′a-tetrahydro-6,3′,7,7′a-diligustilide-8′-one (1), Z,Z′-6,6′,7,3′a-diligustilide (2) and the 8-epimer (3) of 2 on the basis of spectral data. Conclusion Compound 1 is a new dimeric phthalide derivative, and compound 3 was first reported from radix Angelica sinensis.

Antidepressant amides from Piper laetispicum C. DC

Abstract: AIM To investigate the antidepressant constituents of Piper laetispicum C. DC. METHODS The compounds were enriched by column chromatography on silica gel. Structural determination of the pure compounds was based on extensive analyses of modern spectroscopic methods including MS, HR-MS, UV, IR, 1D- and 2D-NMR spectra. The mouse forced swimming test was used for chasing antidepressant activity. RESULTS Three amides were isolated and identified as N-isobutyl-(3,4-methylendioxyphenyl)-2E, 4E, 9E-undecatrienoamide (I), N-isobutyl-9-phenyl-2E, 4E-nonadienamide (II) and N-isobutyl-7-phenyl-2E, 4E-heptadienamide (III). CONCLUSION N-Isobutyl-(3,4-methylendioxyphenyl)-2E, 4E, 9E-undecatrienoamide (I) is a new compound named as laetispicine. N-Isobutyl-9-phenyl-2E, 4E-nonadienamide (II) and N-isobutyl-7-phenyl-2E, 4E-heptadienamide (III) were isolated for the first time as natural substance.

Isolation and characterization of phenylethanoid glycosides from Clerodendron bungei

Abstract: Aim To study the chemical constituents from Clerodendron bungei Steud. Methods The compounds were isolated and purified by various chromatographic techniques and identified by their physicochemical properties and spectral data. Results Ten phenylethanoid glycosides were isolated and identified as clerodendronoside (1), acteoside (2), isoacteoside (3), cistanoside C (4), jionoside C (5), leucosceptoside A (6), cistanoside D (7), campneoside I (8), campneoside II (9), cistanoside F (10). Conclusion Compound 1 is a new phenylethanoid glycoside, while compounds 4-10 are obtained from this plant for the first time.

The chemical constituents of Rhododendron ovatum Planch.

Abstract: AIM To study the chemical constituents of Rhododendron ovatum Planch. METHODS The chemical constituents were isolated and purified by silica gel column chromatography and identified on the basis of their physiochemical and spectral data. RESULTS Seven compounds were isolated and identified. Their structures were established as 3,5,7-trihydroxylchromone 3-O-beta-D-xylopyranoside (I), taraxerol (II), beta-sitosterol (III), betulinic acid (IV), quercetin (V), quercetin-3-O-alpha-L-rhamnopyranoside (VI), and D-glucose (VII). CONCLUSION Compound I is a new compound. Compounds II-VII were isolated from this plant for the first time.

[Effects of acidic oligose on differentially expressed genes in the mice model of Alzheimer's disease by microarray].

Abstract: Aim To investigate the molecular mechanism of protective effect of acidic oligose 971 on Alzheimer's disease mouse model by using microarray. Methods Balb/c mice were randomly divided into control group, beta-AP(25-35) i.c.v. injected group and 971-treated group. The learning-memory ability of mice was tested by Morris water maze experiment. Total RNA of the cerebral cortex was extracted from the mice of each group. cDNA microarrays containing 1176 genes were used to investigate the gene expression pattern of each group. Expressions of 5 genes were randomly selected for further confirmation by RT-PCR. Results Icv injection of beta-AP(25-35) caused significant impairments in spatial and working memory performances of mice in Morris water maze and which were relieved by the treatment of 971. Up- and down- regulated genes were 19 and 12 in beta-AP(25-35)-injected group vs control group, respectively. Up- and down- regulated genes were 13 and 4, respectively, in 971-treated group vs beta-AP(25-35)-injected group. RT-PCR results indicated that 5 genes showed identical results to that of the microarray. Conclusion The protective effect of 971 on learning and memory ability of beta-AP(25-35)-treated mouse may be related to the expression changes of genes involved in cell cycle, DNA repair, nerve growth, synaptic plasticity and immune response, etc.

Effect of PPARgamma agonist rosiglitazone on regression of the atherosclerotic plaques in rabbits

Abstract: AIM To explore the prevention of atherosclerosis by PPARy agonist rosiglitazone. METHODS 24 male New Zealand white rabbits weighing 1.8 to 2.2 kg were randomly divided into 3 groups: control group, normal rabbit chow; cholesterol group, 1% cholesterol diet; rosiglitazone group, 1% cholesterol diet supplemented with rosiglitazone 0.5 mg x kg(-1) x d(-1) for 6 weeks. Rabbits in cholesterol group and rosiglitazone group were sequentially fed 1% cholesterol-containing diet for 16 weeks. At the end of the experiment, blood glucose, serum lipids levels, ratio of plaque area to aorta area and ratio of intima to media were determined. RESULTS Hypercholesterolemia was successfully reproduced in rabbits. Adnimistration of rosiglitazone significantly decreased serum TC and LDL-C. The ratio of intima to media and ratio of plaque area to aorta area were also reduced. CONCLUSION Rosiglitazone could prevent atherosclerosis by decreasing levels of TC and LDL-C.

Deposition of insulin powders for inhalation in vitro and pharmacodynamic evaluation of absorption promoters in rats.

Abstract: Aim To prepare insulin powder for inhalation by spray-drying technology, determine the deposition of the insulin powder formulation in vitro and preliminarily investigate hypoglycemic response of the dry powder with/without absorption promoters. Methods The depositions of the insulin powder for inhalation were determined by the China Pharmacopoeia 2000 version addenda XH and hypoglycemic effects were evaluated by testing serum glucose with glucose oxidase-peroxidase (GOD-PAP) method. Results The depositions of the spray-dried insulin powder for inhalation were more than 40% under various humidity and their changes were not significant when air flow was no less than 18L•min^(-1). The coadministration of insulin with 8L•min^(-1)/dose sodium taurocholate [PA=59.91%, C(subscript nadir)=(33±6)%] and 10mmol•L^(-1)/dose sodium deoxycholate [PA=47.46%, C(subscript nadir)=(32±7)%] induced a significantly greater decline in blood glucose levels, while coadministration with 1% sodium caprylate, 1% sodium dodecyl sulfate, 250μg/dose lecithin, 10mmol•L^(-1)/dose EDTA appeared to have no significant effect (P＞0.05). Conclusion Insulin powder for inhalation was relatively stable under various humidity conditions and different flow current. The use of 8mmol•L^(-1)/dose sodium taurocholate and 10mmol•L^(-1)/dose sodium deoxycholate could be able to potentially improve the bioavailability of insulin by pulmonary route.

[Ginsenoside Rbl attenuates beta-amyloid peptide25-35 -induced tau hyperphosphorylation in cortical neurons].

Abstract: Aim To explore the effect and the possible mechanism of ginsenoside Rb1 on beta-amyloid peptide (beta-AP)(25-35) -induced tau protein hyperphosphorylation in cortical neurons. Methods Western blotting and immunocytochemical staining were used to detect tau phosphorylation level, total tau and glycogen synthase kinase-3beta (GSK-3beta) in cortical neurons. Results After exposure to beta-AP(25-35) (20 micromol x L(-1)) for 12 h, the levels of tau protein phosphorylation in the sites of Ser 396, Ser 199/202, Thr 231 and total tau were raised. Meanwhile, the expression of GSK-3beta also increased. Pretreatment with ginsenoside Rbl or lithium chloride, a specific inhibitor of GSK-3beta, markedly reduced beta-AP(25-35)-induced tau hyperphosphorylation and the expression of GSK-3beta. Conclusion Ginsenoside Rb1 can attenuate beta AP(25-35)-induced tau protein hyperphosphorylation in cortical neurons by inhibiting the expression of GSK-3beta.