Synthesis and antitumor activity of novel tetrahydro-beta-carboline derivatives as KSP inhibitors / 药学学报

Inhibitors of kinesin spindle protein (KSP) are a promising class of anticancer agents that cause mitotic arrest and induce apoptosis of tumor cells. A series of novel tetrahydro-beta-carboline derivatives were synthesized as kinesin spindle protein inhibitor and evaluated as potential antitumor agents. All compounds showed promising KSP inhibitiory activity. Compounds 8 and 9 exhibited better antitumor activity (Lung/A549, Stomach/AGS) than CK0106023 with GI50/IC50 values (1.07/1.62 and 1.46/3.27 micromol x L(-1), 1.09/>10 and 1.22/6.33 micromol x L(-1), respectively).

Effects of recombinant hirudin variant Ⅲ on expression of apoptosis-related genes during galactose-mediated human lens epithelial cells damage / 中华实验眼科杂志

Background Recombinant hirudin variant Ⅲ(rHV3) can effectively prevent galactose-induced human lens epithelial cells LECs injury,but little is known about the molecular mechanism of its action.Objective The present study was to investigate the effects of rHV3 on the expression of apoptosis-related genes in damaged LECs induced by galactose.Methods The rHV3 was extracted by our research group,and the biological activity of rHV3 was identified by titration of thrombase according to Markwardt's method.Human LECs (SRA01/04) were cultured using 125×10-3 mol/L D-galactose+10% FBS+D/F12 medium to establish the damaged human LECs model.rHV3 was added into the medium of the damaged human LECs model.Human LECs were cultured in D/F12 medium containing 10% FBS as normal control.The expression of apoptosis-related genes,such as aldose reductase (AR),bax,bcl2 and p53,in LECs at the mRNA level was detected using RT-PCR.The abundance ratio of target genes was presented with the absorbance (A) of gene mRNA/GAPDH mRNA.Results Compared to the normal control group,the A values of AR mRNA/GAPDH mRNA,bax mRNA/GAPDH mRNA and p53 mRNA/GAPDH mRNA were significantly elevated in model group (t=3.90E-06,t=8.44E-04,t=5.15E-08,P＜0.01).However,in the rHV3-treated group,the A values of AR mRNA/GAPDH mRNA,bax mRNA/GAPDH mRNA and p53 mRNA/GAPDH mRNA were lower than those of model group (t=5.90E-06,t=1.51E-04,t=3.42E-06,P＜0.01).The bcl2 mRNA/GAPDH mRNA was markedly downregulated in the model group when compared with the normal control group (t=1.86E-05,P＜0.01);while after rHV3 addition,bcl2 mRNA/GAPDH mRNA increased in comparison with the model group (t=8.56E-05,P＜0.01).Conclusion 125×10-3mol/L D-galactose induces the damage and apoptosis of human LECs.rHV3 likely plays a protective function on D-galactose-induced damage of human LECs by inhibiting the polyol pathway and mitochondria-mediated pathway.

Primary structure determination of hirudin and reteplase fusion protein by LC/ESI-MS/MS spectrometry / 药学学报

The aim is to determine the primary structure of a new hirudin and reteplase fusion protein (HV12p-rPA) by LC-ESI-MS/MS spectrometry. The molecular weight of the hirudin and reteplase fusion protein (HV12p-rPA) was measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The HV12p-rPA was digested with trypsin and chymotrypsin separately and the peptides in the digest mixtures were identified by LC-ESI-MS/MS. The molecular weight of HV12p-rPA was 41,472 Da, which was in accordance with the theoretical value. The peptide fragments of HV12p-rPA digested with trypsin were identified by LC-ESI-MS/MS spectrometry and the results indicated that the fusion protein contained r-PA. Then, the peptides of HV12p-rPA digested with chymotrypsin were identified by the same method. The results indicated that the fusion protein contained HV12p and the linker-containing peptide, DEGGGSY. MASDF and LDWIRDNMRP were identified as the N-terminal and C-terminal containing peptides in the chymotryptic digest mixture of the fusion protein. All of the Xcorr values exceeded 1.5, some of which were above 3.0, showing that the results were correct and credible and a sequence coverage of 85% was achieved. HPLC/MS analysis coupled with uncompleted digestion indicated that all these peptides were arranged with the correct order as expected. Thus, sequence of the fusion protein was confirmed and it was consistent with our design in upstream construction.

Synthesis and biological evaluation of tetrahydro-beta-carline derivatives / 药学学报

Kinesin spindle protein (KSP/Eg5) is essential for the formation and maintenance of bipolar spindles during mitosis. Inhibition of this protein leads to cell cycle arrest and apoptosis without interfering other microtubule-dependent processes. Therefore, it is a potential target in cancer therapy. Here, a series of tetrahydro-beta-carboline derivatives 5a - k were synthesized as kinesin spindle protein inhibitor. Their structures were confirmed with 1H NMR, ESI-MS and elemental analysis. The synthesized compounds were evaluated for their inhibition of KSP.

Application of HPLC-ESI-ITMS in the quality control of carboxyterminal sequence confirmation for insulin and insulin chain B / 药学学报

Application of HPLC-ESI-ITMS in the quality control of carboxyterminal sequence confirmation for insulin and insulin chain B was studied. The solution of intact insulin or insulin chain B was added to the solution of carboxypeptidase P (CPP) and carboxypeptidase Y (CPY). Fractions of appropriate volume were removed at some appointed time points, acidified with the same amount of 1% formic acid to stop the digestion, and then briefly vortexed for HPLC-ESI-ITMS analysis. Mobile phase A consisted of 0.02% TFA in 98% ultra-pure water and 2% acetonitrile. Mobile phase B consisted of 0.02% TFA in 98% acetonitrile and 2% ultra-pure water. The solution used for post-column fix consisted of propionic acid and isopropyl alcohol (20 : 80, v/v). Chromatographic separation was carried out on a reversed-phase column (Zorbax Prosphere C18, 300A, 5 microm, 2.1 mm ID x 150 mm length). The molecular weights of the multiply charged ions representing consecutive truncated losses of carboxyterminal amino acids were determined by the use of HPLC-ESI-ITMS. The differences between the consecutive truncated peptides are the experimental weights of the carboxyterminal amino acid residues. The carboxyterminal amino acid residue Ala, which released from chain B of intact insulin, was confirmed in the nanomolar concentration range by analyzing the molecular weight of the truncated peptides. Another one carboxyterminal amino acid Ala was confirmed in the nanomolar concentration range of insulin chain B. In the quality control for recombinant DNA product or natural protein, the confirmation of 1 - 3 carboxyterminal amino acid residues is regarded to be up to standard. One amino acid residue of insulin or insulin chain B could be confirmed accurately in the nanomolar concentration range. The results showed that intact insulin could be directly sequenced in the quality control without separating chain B from chain A. There would be no need to separate chain A from chain B to identify carboxyterminal of intact insulin. Furthermore, the method saved us a lot of trouble from the preparation and purification of insulin chain A and chain B.

Protective effects of shark hepatic stimulator substance against acute hepatic injury induced by acetaminophen in mice / 药学学报

<p><b>AIM</b>To investigate the protective effects of shark hepatic stimulator substance (sHSS) against acute hepatic injury induced by acetaminophen (AAP) in mice.</p><p><b>METHODS</b>Acute hepatic injury model of Balb/c mice was induced by a single intraperitoneal injection of AAP (200 mg.kg-1, i.p.). Serum ALT and AST activities were analyzed. The changes of microstructure and ultrastructure of hepatocyte were observed under optical and electronic microscope. The hepatocyte apoptosis was analyzed by flow cytometer and the expression level of Fas mRNA was determined by RT-PCR.</p><p><b>RESULTS</b>The activities of serum ALT and AST were significantly decreased and both necrosis and inflammatory infiltration were improved in the mice treated with sHSS 3.0 and 1.5 mg.kg-1. sHSS (3.0 mg.kg-1) prevented the ultrastructural changes of hepatocytes caused by AAP, decreased the percentage of apoptotic cells, and downregulated the expression level of Fas mRNA.</p><p><b>CONCLUSION</b>sHSS protected hepatocytes from AAP-induced injury, which might be associated with its protection of the mitochondria and inhibition of apoptosis and expression of Fas mRNA in hepatocytes.</p>

Antibody sandwich enzyme-linked immunoadsorbent assay for determination of recombinant E. coli L-asparaginase in rat plasma and its pharmacokinetics / 药学学报

<p><b>AIM</b>To establish antibody sandwich enzyme-linked immunoadsorbent assay for determination of recombinant E. coli L-asparaginase in rat plasma and study its pharmacokinetics.</p><p><b>METHODS</b>A Japanese white rabbit was immunized with recombinant E. coli L-asparaginase. Immunoglobulin G was separated and purified by using DEAE-cellulose chromatography. Conjugation of horseradish peroxidase to immunoglobulin G was obtained using the two-step glutaraldehyde method. Recombinant E. coli L-asparaginase protein in plasma was measured by antibody sandwich enzyme-linked immunoadsorbent assay. Pharmacokinetic parameters were assessed with model-dependent method.</p><p><b>RESULTS</b>The linearities was 1-64 U.L-1. Concentration-time profile after i.v. of 1.25, 2.50, 5.00 kU.kg-1 of recombinant E. coli L-asparaginase fitted with a two-compartment model. The first and terminal elimination T1/2 were 0.50-0.57 h and 2.45-3.02 h, respectively. The AUC was linearly related to the doses.</p><p><b>CONCLUSION</b>Antibody sandwich enzyme-linked immunoadsorbent assay was constant, reliable, sensitive, and suitable for the determination of recombinant L-asparaginase. Pharmacokinetics of recombinant E. coli L-asparaginase in rats is warranted for the design of future clinical trails.</p>