Cytotoxic depsidones and xanthones from Garcinia esculenta Y. H. Li.

Six new compounds, including two depsidones garciculendepsidones A and B (1 and 2), one prenylated xanthone garciculenxanthone (3) and three dimeric xanthones bigarciculenxanthones A-C (4-6), were isolated from the twigs and leaves of Garcinia esculenta Y. H. Li. Their structures were elucidated based on comprehensive analyses of spectral data, including HRESIMS, 1D and 2D NMR, and ECD calculation. All the isolates were tested for their cytotoxicity against five human cancer cell lines (myeloid leukemia HL-60, lung cancer A-549 cells, hepatocellular carcinoma SMMC-7721, breast cancer MDA-MB-231 and colon cancer SW480), among them, compounds 3-5 displayed cytotoxic potential, especially garciculenxanthone (3) had the lowest IC50 value of 8.2 µm for lung cancer A-549 cells.

Hispanane-Type Diterpenoid and Secoiridoid Glucosides from Viburnum cylindricum.

Three hitherto unknown compounds, including one new hispanane-type diterpenoid glucoside, namely viburnumoside (1), two new secoiridoid glucosides, 7α-galloyloxysweroside (2), and 7ß-galloyloxysweroside (3), together with ten known compounds (4 - 13) were isolated from the ethanol extract of twigs and leaves of Viburnum cylindricum. Their structures were elucidated on the basis of extensive spectroscopic studies, and the absolute configuration of compound 1 was confirmed by the experimental and calculated electronic circular dichroism (ECD) data.

Clerodane Diterpenoids with Anti-hyperglycemic Activity from Tinospora crispa.

Four new clerodane diterpenoids, tinosporols A-C (2-4) and tinosporoside A (5), together with six known analogues were isolated from the vines of Tinospora crispa. Their structures were established by extensive spectroscopic analysis. The relative configuration at C-12 in the known diterpenoid borapetoside E (1), the major component of the plant, was firstly established with the aid of molecular model. Compound 1 significantly reduced serum glucose levels at dose-dependent manners in alloxan-induced hyperglycemic mice and db/db type 2 diabetic mice.

Implantation of hydroxyapatite-titanium corneal implants in rat cornea.

PURPOSE: To evaluate the biocompatibility of hydroxyapatite-coated titanium (HA/Ti) corneal implants at the molecular levels with histopathology. METHODS: Eighty Sprague-Dawley rats were divided into 2 equal groups. In the study group, HA/Ti prosthetics were implanted into the right corneal stroma. The control group received a sham incision. Corneas were collected and studied with histopathological examination (HE), immunohistochemical, and other stains, including scanned electron microscopy and reverse transcription-polymerase chain reaction, to evaluate inflammatory reactions, tissue repair, and expression of various biological factors during healing. RESULTS: In the control group, corneal neovascularization occurred 7 days after surgery, and the corneas recovered 28 days after surgery. In the study group, corneal vascularization increased substantially on day 7 and stabilized on day 28. For both groups, reverse transcription-polymerase chain reaction detected expressions of 6 primers at all time points. The amplified sequences were consistent with the designed sequences. The expression of matrix metalloproteinase-2, matrix metalloproteinase-9, bFGF, vascular endothelial growth factor, and type III collagen were delayed in the study group compared with the control group. Histological analyses showed a tight attachment of the corneal tissue to the HA/Ti implant on day 28. CONCLUSIONS: The HA/Ti corneal implants can remain stable in corneal tissue for a long time, induce corneal neovascularization, and stimulate inflammatory cells and keratocytes to synthesize or activate matrix metalloproteinases. Artificial cornea made from this material show enhanced stability and biocompatibility in vivo.