Gαq-protein carboxyl terminus imitation polypeptide GCIP-27 attenuates proliferation of vascular smooth muscle cells and vascular remodeling in spontaneously hypertensive rats.

Gq-protein is located at the convergent point in signal transduction pathways leading to vascular remodeling. The carboxyl terminus of Gα-subunit plays a vital role in G-protein-receptor interaction. The present study was designed to explore the effects of a synthetic Gαq carboxyl terminus imitation peptide, namely GCIP-27, on vascular smooth muscle cells (VSMC) in vitro and vascular remodeling in spontaneous hypertensive rats (SHR). Hyperplasia and hypertrophy of VSMC wre determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, [(3)H]-thymidine and [(3)H]-leucine incorporation, and [Ca(2+)](i) was measured with Fluo-3/AM staining. Systolic blood pressure (SBP), the ratio of media thickness to lumen diameter (MT/LD) of aorta, collagen content, and phospholipase C activity in aorta were measured in SHR. GCIP-27 (3-100 µg/l) significantly decreased proliferation activity, protein content, incorporation of [(3)H]-thymidine and [(3)H]-leucine, and [Ca(2+)](i) level in VSMC. SBP, MT/LD, collagen content, and phospholipase C activity in aorta of SHR were decreased significantly in GCIP-27 (7, 20, 60 µg/kg)-treated groups and losartan (6 mg/kg) group compared with vehicle group. In conclusion, GCIP-27 could inhibit vascular remodeling effectively in vitro and in vivo.

[Studies on chemical constituents of alpinia katsumadai].

OBJECTIVE: To study the chemical constituents from the ethanolic extract of Alpinia katsumadai Hayata. METHODS: The compounds were separated with the column chromatographic, and their structures were identified by chemical and spectroscopic methods. RESULTS: Eight compounds were isolated from the ethanol extract. On the basis of their physical and chemical properties and spectroscopic analysis, the structures of seven compounds were identified. They were 1,7-Diphenyl-5-hydroxy-4, 6-heptadien-3-one(I), 1,7-Diphenyl4, 6-heptadien-3-one(II), Pinocembrin (III), Cardamomin (IV), Alpinetin (V), 7,4'-Dihydroxy-5-methoxy flavanones(VI) and beta-Sitosterol(VIII), respectively. CONCLUSION: Compounds I , II and VII are separated from this plant for the first time. Compounds I and II are also obtained from this genus of Alpinetin for the first time.

[The anti-respiratory syncytial virus effect of active compound of Glycyrrhiza GD4 in vitro].

OBJECTIVE: To study the effect on anti-respiratory syncytial virus of an active compound GD4 from Glycyrrhiza in vitro. METHODS: GD4 was extracted from Glycyrrhiza by hot water extraction, dichloromethane extraction and column chromatography. The CPE inhibition assay was used to test the antiviral activity of GD4 on RSV in Hela cells. RESULTS: GD4 was effective antiviral agent for RSV in a concentration-dependent manner and its median toxic concentration (TC50) and median effeicacious concentration (EC50) and treatment index (TI) was 0.23 mg/ml, 28.73 microg/ml and 8.0. 120 microg/ml GD4 exhibited inhibitory effect when added into cell culture for every 2h within 12h post-infection. GD4 didn't contain glycyrrhizic acid. CONCLUSION: The active compound of Glycyrrhiza (GD4) was an evident inhibitory effect on RSV.

Down-regulation of gut-enriched Kruppel-like factor expression in esophageal cancer.

AIM: Esophageal carcinoma is one of the most common malignant tumors in China. But the molecular mechanisms of esophageal carcinoma remains unclear. Gut-enriched Kruppel-like factor (GKLF) is a newly identified transcription factor which is expressed abandantly in the epithelial cells of the gastrointestinal tract and deregulation of GKLF was linked to several types of cancer. It is of interest to study the expression and role of GKLF in esophageal carcinoma. METHODS: Semi-quantitative RT-PCR was used to compare GKLF expression in esophageal squamous cell carcinoma to normal mucosa of the same patients. The serum deprivation inducibility of GKLF was observed in an esophageal squamous cancer cell line by comparison to the primary culture of human fibroblast. The effect of antisense GKLF transfection on the proliferation and adhesion of esophageal squamous cancer cell line was also observed. RESULTS: The level of GKLF transcript is lower in esophageal squamous cell carcinoma compared to paired normal-appearing mucosa in 14 of 17 of the tumors analyzed. The serum deprivation inducibility of GKLF was greatly decreased in an esophageal squamous cancer cell line compared to the primary culture of human fibroblast. Decreased expression of GKLF in the esophageal cancer cell by antisense GKLF transfection increased its proliferation rate compared with that of vector transfected cell control (P<0.05). Transfection of antisense GKLF decreased its adhesion ability (P<0.05). CONCLUSION: The findings of this study demonstrate the down-regulation of GKLF in esophageal squamous cancer, and suggest that deregulation of GKLF may play a role in initiation and/or progression as well as the metastasis of esophageal squamous cancer.