[Effects of Tongbi capsule on joint lesions in rabbits with rheumatoid arthritis].

The purpose of this experiment is to observe the effects of Tongbi capsule on joint lesions in rabbit with rheumatoid arthritis induced by ovalbumin and explore the mechanism in order to provide reference for clinical application of Tongbi capsule. Rheumatoid arthritis in rabbits was induced by subcutaneous injection of emulsions of ovalbumin and Freund's complete adjuvant and intra articular injection of ovalbumin. After successful modeling, 30 New Zealand rabbits with arthritis were randomly divided into model control group, the high, medium and low dose groups of Tongbi capsule (90, 45, 22.5 mg·kg⁻¹) and prednisone group (5 mg·kg⁻¹). Another six normal rabbits were used as normal control group. After 24 hours of modeling, the rabbits in Tongbi capsule groups received intragastric (i.g.) administrations of Tongbi capsule at 90, 45, 22.5 mg·kg⁻¹·d⁻¹, and the rabbits of prednisone group received i.g. administrations of prednisone at 5 mg·kg⁻¹·d⁻¹ for 2 weeks. The rabbits in normal and model groups received the same volume of distilled water at the same time. The swelling degree of rabbit knee joint and local skin temperature were observed daily. After two weeks of administration, pathological changes of rabbit knee joint were examined by magnetic resonance imaging (MRI); the morphological changes of articular cartilage and synovial membrane were observed by microscope; and the contents of interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-α) in serum were detected by enzyme linked immunosorbent assay (ELISA).The results showed that 24 h after modeling, the knee joints of the rabbits were swollen, with red or dark redlocal skin, and fever, elevated local skin temperature and increased diameters of knee joints. Two weeks after modeling, the swelling of rabbit knee joints was obvious in model group; the joint cavities were filled with purulent fluid; joint synovial membranes were obviously thickened, and even joint cavities were fibrotic and cartilage surfaces showed slight defect; the surface of articular cartilage was obvious fibrosis; synovial epithelial cell proliferation was obvious and accompanied by extensive inflammatory cell infiltration; the levels of IL-1 and TNF-α were significantly higher as compared with those seen in model rabbits (P<0.05, P<0.01). After 1 and 2 weeks of administration, knee joint diameters and local skin temperatures were smaller or lower than thosein model group (P<0.05, P<0.01); The lesions of joint cartilage and synovial of all rabbits in each group were less than those in model group; IL-1 and TNF-α levels in serum were also lower than those in model group (P<0.05, P<0.01). The results reveal that high and medium doses of Tongbi capsule can suppress rheumatoid arthritis induced by ovalbumin in rabbits, reduce joint swelling, inhibit synovial epithelial and fiber hyperplasia and inflammatory cell infiltration, and alleviate articular cartilage damage. The mechanism may be associated with decreasing IL-1 and TNF-α levels in serum.

New sesquiterpenes from the rhizomes of homalomena occulta.

Six new sesquiterpenes (1-6), along with eight known ones (7-14) were isolated from the rhizomes of Homalomena occulta. Structure elucidation of the new compounds was achieved through 1D NMR, 2D NMR spectroscopic techniques and HRESIMS, while the absolute configurations of compounds 1, 2 and 5 were confirmed by X-ray crystallographic analysis. All of the isolates were evaluated for their activity against LPS-induced production of nitrogen oxide (NO) in macrophage cells, and compounds 1 and 5 showed inhibitory effect on NO production with the IC50 values of 21.2 and 15.4 µM, respectively.

Design of gem-difluoro-bis-tetrahydrofuran as P2 ligand for HIV-1 protease inhibitors to improve brain penetration: synthesis, X-ray studies, and biological evaluation.

The structure-based design, synthesis, biological evaluation, and X-ray structural studies of fluorine-containing HIV-1 protease inhibitors are described. The synthesis of both enantiomers of the gem-difluoro-bis-THF ligands was carried out in a stereoselective manner using a Reformatskii-Claisen reaction as the key step. Optically active ligands were converted into protease inhibitors. Two of these inhibitors, (3R,3aS,6aS)-4,4-difluorohexahydrofuro[2,3-b]furan-3-yl(2S,3R)-3-hydroxy-4-((N-isobutyl-4-methoxyphenyl)sulfonamido)-1-phenylbutan-2-yl) carbamate (3) and (3R,3aS,6aS)-4,4-difluorohexahydrofuro[2,3-b]furan-3-yl(2S,3R)-3-hydroxy-4-((N-isobutyl-4-aminophenyl)sulfonamido)phenylbutan-2-yl) carbamate (4), exhibited HIV-1 protease inhibitory Ki values in the picomolar range. Both 3 and 4 showed very potent antiviral activity, with respective EC50 values of 0.8 and 3.1 nM against the laboratory strain HIV-1LAI . The two inhibitors exhibited better lipophilicity profiles than darunavir, and also showed much improved blood-brain barrier permeability in an in vitro model. A high-resolution X-ray structure of inhibitor 4 in complex with HIV-1 protease was determined, revealing that the fluorinated ligand makes extensive interactions with the S2 subsite of HIV-1 protease, including hydrogen bonding interactions with the protease backbone atoms. Moreover, both fluorine atoms on the bis-THF ligand formed strong interactions with the flap Gly 48 carbonyl oxygen atom.

[Anthraquinones and triterpenoids from roots of Knoxia roxburghii].

Nine compounds were isolated from an ethanol extract of the roots of K. roxburghii by using a combination of various chromatographic techniques including column chromatography over silica gel, MCI gel, Sephadex LH-20, and reversed-phase HPLC. On the basis of physical-chemical properties and spectroscopic data analysis, their structures were identified as munjistin (1), 1-methoxy-3,6-dihydroxy-2-hydroxymethyl-9,10-anthraquinone (2), 1,2,3-trihydroxy-9,10-anthraquinone (3), arjunolic acid (4), hyptatic acid-A (5), hyptatic acid-B (6), 2α,3ß,24-trihydroxyurs-12-en-28-oic acid (7), 2α,3ß,23-trihydroxyurs-12-en-28-oic acid (8), and daucosterol (9). Compounds 1-9 were obtained from this genus for the first time.

[Effect of panax notoginseng powder on pathological features and expressions of VEGF and its receptors of chronic subdural hematoma rabbits: an experimental study].

OBJECTIVE: To observe the effect of Panax notoginseng (PN) on pathological features in chronic subdural hematoma (CSDH) rabbits and its mechanisms. METHODS: A stable pathological animal model similar to CSDH in humans could be established using subdural injections of small number of blood through a subdural pre-catheter in rabbits. After successful modeling, 18 rabbits were randomly divided into the model group, the low dose PN group (0.125 g/kg), and the high dose PN group (0.250 g/kg), 6 in each group. Normal saline was given to rabbits in the model group, while PN power was given to those in the PN groups by gastrogavage for 6 successive days. Pathologic features of the hematoma outer membrane were observed by HE staining. The activity of SOD and the content of MDA in the hematoma outer membrane were examined by the colorimetric method. Expressions of CD31, CD34, and VEGF in the hematoma outer membrane were observed by immunohistochemical assay. Expressions of VEGF in the peripheral blood and the subdural hematoma were detected by enzyme-linked immunosorbent assay (ELISA). Expressions of VEGFR-1 and VEGFR-2 in the hematoma outer membrane were detected by Western blot. RESULTS: Compared with the model group, the inflammatory reaction was comparatively lessen and the proliferation of the fibrous tissue was relatively mature in the low and high dose PN groups. The activity of SOD increased (P < 0.05); expressions of CD31 and CD34 were reduced (P < 0.01); VEGF expression in the residual hematoma fluid decreased (P < 0.05) in the high dose PN group. Expressions of VEGF and VEGFR-2 were all reduced in the high and low dose PN groups (P < 0. 05, P < 0.01). Compared with the low dose PN group, expressions of CD31 and CD34 were reduced (P < 0.01), and the VEGFR-2 expression was also reduced (P < 0.05) in the high dose PN group. CONCLUSIONS: PN could promote the fibrous repairing of subdural hematoma in CSDH rabbits. It also lessened inflammation and oxidative injury of the hematoma outer membrane and reduced expressions of VEGF. The pathological angiogenesis could be reduced through influencing VEGFR-2 receptor pathways, which might be an important mechanism.