1.Anti-tumor activity and mechanism of new microtubuIe-targeting compound WX-127-07
Fang GUAN ; Long LONG ; Wei LL ; Fan FENG ; Feifei LL ; Lan XLE ; Lili WANG
Chinese Journal of Pharmacology and Toxicology 2014;(5):702-712
OBJECTIVE To evaluate the anti-tumor activities of WX-127-07,a new microtubule-tar-geting agent invitroand probe its molecular mechanism. METHODS The well-known microtubule-targe-ting anti-tumor drugs taxol,vincristine and anti-gout drug colchicine were used as positive controls. The anti-proliferation activity was examined in five different cell lines after treatment with WX-127-07(0.3 -300 nmol·L-1 )for 72 h by SRB assay. The cell cycle arrest profile was assayed by flow cytometry. The multiparameters of cytotoxicity,cell morphology,apoptosis and different signaling pathways related to tumorigenesis and inflammation were analyzed using the high content analysis platform. Tubulin tryptic digestion and competition inhibition assay for colchicine or vinblastine site were used to confirm the bind-ing site in microtubules at a molecular level. RESULTS All the tested compounds obviously inhibited the growth of A549,HepG2,HeLa,HLF and HUVEC cells. The lC50 values of WX-127-07 were 4.47±0.05, 5.18±0.08,4.90±0.19,4.10±0.16 and(5.04±0.08)nmol·L-1 respectively,lower than those of colchicine〔the lC50 values were 21. 17 ± 1. 22,14. 19 ± 0. 53,43. 80 ± 1. 64,145. 89 ± 10. 97 and( 27. 67 ± 1.79)nmol·L-1 ,respectively〕and those of vincristine〔the lC50 values were 16.51±0.36,16.76±0.33, 27.80±2.75,43.80±1.48 and(9.15±0.78)nmol·L-1 ,respectively〕,but were similar to or lower than those of taxol〔the lC50 values were 10. 68 ± 0. 61,12. 86 ± 0. 25,4. 81 ± 0. 61,102. 07 ± 15. 17 and( 3. 04 ± 0.12)nmol·L-1 ,respectively〕. High content multi-parameter analysis revealed that WX-127-07 induced a concentration-dependent microtubular depolymerization(P=0.0075)with the same pattern as colchicine and vincristine,but at a lower concentration. Both WX-127-07 and positive drugs could induce cell cycle arrest in A549 cells,increase nuclear membrane permeability and early signs of apoptosis in HepG2 cells,but neither cancer related pathways nor inflammation related pathways were affected. Microtubular competition inhibition assay showed that WX-127-07 inhibited the binding of colchicine with tubulin(P =0.0259). Tryptic digestion of tubulin-WX-127-07 premixture showed a similar electrophoretic band to that of tubulin-colchicine premixture. CONCLUSION WX-127-07 is a novel microtubule-depolymerizing agent with anti-proliferation activity and acting on the colchicine binding site.
2.Effect of doxazosin and metoprolol on vascuIar remodeling in rats with hypertension induced by abdominal aorta coarctation
Lishuang HUANG ; Weili LLU ; Jingbo GONG ; Xiujie GAO ; Yun ZHAO ; Jing MA ; Fang XLE ; Tao ZHANG ; Kaiqi TLAN ; Lin YAO ; Lingjia QLAN
Chinese Journal of Pharmacology and Toxicology 2015;(2):208-212
OBJECTIVE To investigate the effect of doxazosin(DOX) and metoprolol( MET) on vascular remodeling in rats with abdominal aorta coarctation (AAC). METHODS An animal model was established by AAC. Two weeks later, the rats were treated with DOX (10 mg.kg-1 per day) or MET (20 mg.kg-1 per day) for six weeks. Blood pressure was measured using carotid artery intubation with a MP150 polygraph. The media thickness, wall cross-sectional area and thickness / internal diameter ratio were calculated by morphometry. Vascular fibrosis was evaluated by Masson′s trichrome staining. The collagen and fibronectin expression in vascules was measured by Western blotting. RESULTS Compared with the sham group 〔(17.6±0.5)kPa〕, the mean arterial blood pressure in the model group〔(23.3±0.7)kPa〕 was significantly increased(P<0.05), but was lowered by DOX 〔(20.5±0.7)kPa〕 and MET 〔(19.0±0.4) kPa〕 (P<0.05). Moreover, HE staining showed that tunica media thickness, artery vessel area and thickness / inner diameter in the model group were increased by 39.5%, 46.4% and 27.0%(P<0.05), respectively. The tunica media thickness was decreased by 16.0% and 26.1%( P<0.05), respectively, the artery vessel area by 22.8% and 26.1%(P<0.05), respectively, and the thick-ness / inner diameter by 17.0% and 26.0%( P<0.05) when the rats were treated with DOX and MET. Masson staining showed that the collagen accumulation in vascules increased, suggesting that AAC induced fibrosis. Meanwhile, vascular fibrosis induced by AAC was also reduced by MET or DOX. Western blotting also proved that the increase of collagen and fibronectin induced by AAC could be attenuated by DOX and MET(P<0.05). CONCLUSION DOX and MET are effective in suppressing the role of norepi-nephrine in vassels, which can attenuate AAC-induced vassels remodeling by preventing the binding between norepinephrine and adrenoceptors.