Evaluation and SAR analysis of the cytotoxicity of tanshinones in colon cancer cells / 中国天然药物

AIM@#This study was designed to evaluate the anti-cancer actions of tanshinone I and tanshinone IIA, and six derivatives of tanshinone IIA on normal and cancerous colon cells. Structure activity relationship (SAR) analysis was conducted to delineate the significance of the structural modifications of tanshinones for improved anti-cancer action.@*METHOD@#Tanshinone derivatives were designed and synthesized according to the literature. The cytotoxicity of different compounds on colon cancer cells was determined by the MTT assay. Apoptotic activity of the tanshinones was measured by flow cytometry (FCM).@*RESULTS@#Tanshinone I and tanshinone IIA both exhibited significant cytotoxicity on colon cancer cells. They are more effective in p53(+/+) colon cancer cell line. It was also noted that the anti-cancer activity of tanshinone I was more potent and selective. Two of the derivatives of tanshinone IIA (N1 and N2) also exhibited cytotoxicity on colon cancer cells.@*CONCLUSION@#The anti-colon cancer activity of tanshinone I was more potent and selective than tanshinone IIA, and is p53 dependent. The derivatives obtained by structural modifications of tanshinone IIA exhibited lower cytotoxicity on both normal and colon cancer cells. From steric and electronic characteristics point of view, it was concluded that structural modifications of ring A and furan or dihydrofuran ring D on the basic structure of tanshinones influences the activity. An increase of the delocalization of the A and B rings could enhance the cytotoxicity of such compounds, while a non-planar and small sized D ring region would provide improved anti-cancer activity.

Granulocyte colony stimulating factor attenuated myocardial apoptosis via Janus kinase 2/signal transducer and activator of transcription signal transduction pathway in rats with coronary microembolization / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effects of granulocyte colony stimulating factor (G-CSF) on myocardial apoptosis following coronary microembolization (CME) and possible role of Janus kinase/singnal transducer and activator of transcription (JAK/STAT) pathway in this process.</p><p><b>METHODS</b>A total of 92 male Sprague Dawley rats were randomized into CME (n = 24), G-CSF (100 microg x kg(-1) x d(-1) i.p. 2 hours post CME for 5 days, n = 24), JAK2 inhibitor AG490 (G-CSF plus AG490, 5 mg x kg(-1) x d(-1) i.p. 2 hours post CME for 5 days, n = 24), all rats received left ventricular injection of homologous microthrombotic particle suspension post clamping the ascending aorta. Sham-operated group (n = 20) served as control. The rats were sacrificed at day 3, 7, 14 and 28 after operation. The myocardial mRNA expressions of Bcl-2, Bax, Fas, FasL and GAPDH which was used as the intercomparison, were evaluated by real time PCR. The ratio of Bcl-2/Bax was compared. The protein expression of Caspase-3, cleaved PARP, t-JAK2, p-JAK2, t-STAT3 and p-STAT3 were detected by western blot. Myocardial apoptosis were examined by TUNEL staining.</p><p><b>RESULTS</b>Compared with Sham rats, the mRNA of Bcl-2, Bax, Fas and FasL significantly increased whereas the ratio of Bcl-2/Bax (0.28 +/- 0.04 vs. 2.98 +/- 0.49) significantly decreased and the protein expression of Caspase-3 (0.762 +/- 0.129 vs. 0.133 +/- 0.027), PARP (0.992 +/- 0.146 vs. 0.386 +/- 0.074) and the myocardial apoptosis index (17.2 +/- 1.9 vs. 1.2 +/- 0.6) significantly increased in CME hearts (all P < 0.05). rhG-CSF significantly attenuated CME induced changes and cotreatment with JAK2 inhibitor AG490 abolished the effects of rhG-CSF. The protein expressions of t-JAK2 and t-STAT3 among the groups were similar. P-JAK2 and p-STAT3 protein expressions were significantly increased in G-CSF group compared to other groups (P < 0.05).</p><p><b>CONCLUSION</b>G-CSF attenuated myocardial apoptosis induced by CME via JAK2/STAT3 pathway.</p>

Firebird and cypher sirolimus-eluting stents and bare metal stents in treatment of very long coronary lesions / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>As a kind of sirolimus-eluting stent (SES) made in China, Firebird SES is more effective than bare metal stent (BMS) and not inferior to Cypher SES for short coronary lesions in terms of reduction of restenosis and revascularization. However, Firebird SES does not show any benefits in patients with a very long coronary lesion (VLCL). The present study was undertaken to evaluate the safety and efficacy of Firebird SES for VLCL by comparison of Cypher SES and BMS.</p><p><b>METHODS</b>In this prospective, nonrandomized and comparative study, eligible patients with de novo coronary lesion (> or = 30 mm) between January 2005 and June 2006 were allocated into Firebird SES group, Cypher SES group or BMS group. They were subjected to an angiographic follow-up of 6 months and a clinical follow-up of 12 months. The primary endpoints constitute the in-stent and in-segment restenosis rates at 6 months. The secondary endpoint was defined as a major adverse cardiovascular event (MACE) that was a 12-month combined endpoint of all-cause deaths, reinfarction or in-stent thrombosis, and target-lesion revascularization. The 12-month in-stent thrombosis was also evaluated to address the safety of Firebird SES implantation exceptionally.</p><p><b>RESULTS</b>A total of 468 patients were assessed for eligibility. Of 113 patients who were finally included according to the prior inclusion and exclusion criteria, 39 (41 lesions) were treated with Firebird SES, 37 (39 lesions) with Cypher SES, and 37 (37 lesions) with BMS. There were no significant differences in the baseline characteristics between the three groups; but there were longer lesions, more frequent use of overlapping stent in the Firebird SES group and the Cypher SES group. Angiographic follow-up showed that the rates of binary stenosis were similar between the Firebird SES group and the Cypher SES group (in-segment: 14.6% vs 12.8%, relative risk (RR) 1.14, P = 0.81; in-stent: 9.8% vs 10.3%, RR 0.95, P = 0.94), and significantly lower than those in the BMS group (in-segment: vs. 36.1%, RR 0.41 or 0.36, P = 0.04 or 0.03, respectively; in-stent: vs 30.6%, RR 0.32 or 0.34, P = 0.03 or 0.04, respectively). The total MACE rate up to 12 months was also similar in both SES groups (7.7% vs 5.4%, P = 1.000), and significantly lower than that in the BMS group (27.0%, P = 0.034 or 0.024, respectively). The in-stent thrombosis rate in the follow-up period was 2.6% in the Firebird SES group, not higher in the Cypher SES and BMS groups (2.7% and 2.7%, respectively, P = 1.000).</p><p><b>CONCLUSIONS</b>In the treatment of VLCL, Firebird SES would be safer and more effective than BMS. Firebird SES may be not inferior to Cypher SES in terms of restenosis and MACE.</p>

Time course of myocardial NF-kappaB activation post coronary microembolization / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the time course of myocardial NF-kappaB activation and association with cardiac function and other pro-inflammation cytokines following coronary microembolization (CME).</p><p><b>METHODS</b>CME was induced by homologous microthrombotic particle suspension injection into left ventricle with simultaneous short-term ascending aorta clamping. The CME rats were randomized to untreated group and pyrrolidine dithiocarbamate (PDTC, a specific NF-kappaB inhibitor) treated group (n = 32 respectively). The rats were sacrificed on day 1, 3, 7 and 14 post-operationally (n = 8 each). Twenty-four rats were sham-operated and served as controls. NF-kappaB DNA-binding activity was evaluated by electrophoretic mobility shift assay (EMSA), protein expressions of TNFalpha, IL-6 and ICAM-1 were analyzed by Western blotting, the dynamic alterations of TNFalpha, IL-6 and ICAM-1 mRNA were quantitatively assessed by Real-time PCR post hemodynamic measurements.</p><p><b>RESULTS</b>NF-kappaB DNA-binding activity in CME group was significantly increased than that of sham group on day 1, peaked at day 3 and was similar as that in sham rats on day 14. The protein and mRNA expressions of TNFalpha, IL-6 and ICAM-1 were significantly increased in CME group at various time points compared those in sham rats. NF-kappaB DNA-binding activity positively correlated with mRNA expressions of TNFalpha, IL-6, ICAM-1, respectively (r = 0.72, P < 0.05; r = 0.94, P < 0.01; r = 0.62, P < 0.05). PDTC significantly suppressed protein and mRNA expressions of TNFalpha, IL-6 and ICAM-1 (P < 0.05) and improved left ventricular function.</p><p><b>CONCLUSION</b>NF-kappaB activation post CME could upregulate the gene transcriptions of TNFalpha, IL-6, ICAM-1 and enhance inflammatory responses and aggravate left ventricular dysfunction.</p>