Résumé
Glycyrrhetinic acid is a major active ingredient in licorice, a famous traditional Chinese medicine. Many studies on its anti-tumor activities and low toxicity to normal cells have attracted a great deal of attention. Reports indicated that glycyrrhetinic acid inhibited the growth of tumor cells through inducing apoptosis, differentiation and the block of cell cycle, suppressing tumor metastasis, reversing the multidrug resistance. Glycyrrhetinic acid also presented synergistic effects combined with chemotherapeutics and could inhibit the carcinogenesis induced by carcinogen. With further studies on mechanism of anticancer actions, glycyrrhetinic acid is being expected to have a good prospect of development and application for cancer therapy.
Sujets)
Humains , Antinéoplasiques , Pharmacologie , Apoptose , Cycle cellulaire , Énoxolone , Pharmacologie , Invasion tumoraleRésumé
Angiotensin I-converting enzyme (ACE, EC3.4.15.1) plays an important role in regulating blood pressure. The C-domain of ACE has been identified as the main catalytic site of angiotensin I cleavage in vivo. The ACE gene fragment of the C-domain was amplified by PCR and cloned into the pPIC9K secretory expression plasmid. The recombinant plasmid was transformed into Pichia pastoris strain GS115. Positive clones were selected and subject to electroporation. Antibiotic G418 was used for the screening of multicopy inserts. After optimization of the expression system, the protein yield reached 0.5 g/L by flask-shaking culture fermentation, and enzyme activity reached 7.178 U/mL in the fermentation supernatant. The purity of the target protein obtained was 97% after Ni+ affinity chromatography. Enzyme inhibitory activity assay using Captopril showed that it is promising to use ACE-C domain as new generation of target for screening ACE inhibitor antihypertensive drugs.
Sujets)
Humains , Inhibiteurs de l'enzyme de conversion de l'angiotensine , Domaine catalytique , Génétique , Électroporation , Peptidyl-Dipeptidase A , Génétique , Pichia , Génétique , Métabolisme , Protéines recombinantes , GénétiqueRésumé
Angiotensin converting enzyme (ACE, EC 3.4.15.1) is a membrane-bound, zinc dependent dipeptidase that catalyzes the conversion of the decapeptide angiotensin I to the potent vasopressor ocatapeptide angiotensin II, by removing two C-terminal amino acids. ACE is well known as a key part of the renin angiotenisn system that regulates blood pressure, and its inhibitors have potential for the treatment of hypertension. This paper reviewed the characteristics of ACE in aspects of its structure-function relationship, gene polymorphism and inhibitor development. In particular, the catalytic mechanisms of the two active sites of somatic ACE in the cleavage of angiotensin I and bradykin are different. Therefore, it would likely provide a new way for exploiting novel ACE inhibitors with fewer side-effects by specifically-targeting the individual active sites of somatic ACE.
Sujets)
Humains , Inhibiteurs de l'enzyme de conversion de l'angiotensine , Pharmacologie , Antihypertenseurs , Pharmacologie , Peptidyl-Dipeptidase A , Chimie , Génétique , Métabolisme , Polymorphisme génétique , Relation structure-activitéRésumé
Objective To study the therapeutic effect of Jiedu Quyu Formula (Formula for Removing Toxins and Blood Stasis) on psoriasis vulgaris of progressive stage and its mechanism. Methods The 70 patients of progressive psoriasis vulgaris were randomized into treatment group (35 cases), treated by Jiedu Quyu Formula, and control group (35 cases), treated by Compound Qingdai Capsule. Healthy control group was of 30 healthy subjects. The contents of plasma endothelin (ET) were determined before and after treatment respectively, and the therapeutic effect of both treated groups were observed. Results After treatment, the psoriasis area and severity index (PASI) of both treated groups were significantly decreased in comparison with before treatment (P