Anti-cisplatin-induced Renal-injury Effect of Human Manganese Superoxide Dismutase with Leader Peptide / 肿瘤防治研究

Objective To investigate the effect of the fusion of leader peptide on the structure of human manganese superoxide dismutase (SOD2) and anti-cisplatin (DDP)-induced renal injury. Methods The effect of mitochondrion targeting sequence (MTS) on the structure and activity of SOD2 was analyzed by structure prediction and superoxide dismutase (SOD) specific-activity determination. The DDP injury model of Kunming (KM) mice was established, and amifostine (AMFT) was set as a positive control. Indicators such as kidney index, renal function, kidney antioxidant capacity, and appearance and pathology changes of mice kidney were used to evaluate the effect of MTS-SOD2 against DDP-induced kidney injury. Results The MTS leader peptide seemed to change the secondary and tertiary structures of SOD2 to some extent, but it also increased the specific activity of the MTS-SOD2 protein. Pre-administration of a medium dose of MTS-SOD2 (0.84 mg/kg) before the use of DDP significantly reduced the level of renal malondialdehyde and increased the SOD activity and total antioxidant capacity (T-AOC) in the kidney, thereby reducing the renal pathological damage and consequently maintaining renal function. The overall protective effect of MTS-SOD2 was comparable to or even better than that of 200 mg/kg AMFT. Conclusion The MTS leader peptide enhances the activity of SOD2 and confers it with an excellent anti-DDP-induced renal-injury effect because of its transmembrane function.

Purification and characterization of two PR-10 protein isoforms from the crude drug of Angelica sinensis / 生物工程学报

Two proteins of similar molecular weight (named as ASPR-C-1 and ASPR-C-2) from the crude drug of Angelica sinensis were purified and characterized by 80% ammonium sulfate precipitation, Sephadex G-50 gel filtration chromatography, and DEAE-Sepharose anion exchange chromatography. The molecular weight of ASPR-C-1 and ASPR-C-2 on SDS-PAGE was 17.33 kDa and 17.18 kDa, respectively. They were mainly monomeric in solution, but partially formed dimers and they were glycoproteins with glycosyl content of 2.6% and 8.2%, respectively. Both ASPR-C-1 and ASPR-C-2 were identified to be members of pathogenesis-related 10 family of proteins by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and have ribonuclease activities with the specific activity of 73.60 U/mg and 146.76 U/mg, respectively. The optimum pH of the two isoforms was similar, at about 5.6, while their optimum temperatures were different. The optimum temperature of ASPR-C-1 was 50 ℃, and that of ASPR-C-2 was 60 ℃. Both isoforms presented highest thermal stability at 60 ℃. However, ASPR-C-2 was more thermotolerant than ASPR-C-1. The latter was rapidly inactivated and retained only about 20% residual activity while the former still maintained about 80% of its original activity at a higher treatment temperature (80 to 100 ℃). In addition, Fe²⁺ had an activating effect on the ribonuclease activities of two isoforms while Ca²⁺, Mg²⁺, Zn²⁺, Mn²⁺, Ag⁺, Cu²⁺, EDTA (Elhylene diamine tetraacetic acid), dithiothreitol and sodium dodecylsulphate showed different degrees of inhibition of the enzyme activities. Our findings provide a foundation for further research on the biological function of PR-10 protein from Angelica sinensis.

Study on quality standard for Jinzhitai Capsule / 中成药

Objective: To establish a quality standard for Jinzhitai Capsule(Rhizoma Polygonati, Radix Polygoni Multiflori Preparata, Rhizoma Alismatis, alcohol extract of Gynostemma Pentaphyllun, Fructus Crataegi, Semen Cassiae, etc.). Methods: Radix Polygoni Multiflori Preparata, Rhizoma Alismatis, Semen Cassiae were identified by TLC. The content of emodin and chrysophand and physcion in Jinzhitai Capsule were determined by HPLC, using a Kroma. sil C 18 column, methanol 0.1% phoaphoeic acid(94∶6) as the mobile phase. The detection wavelength was 440nm. Results: The TLC spots developed were quite clear. The linear ranges of emodin and chrysophanol and physcion were 0.039～0.35?g and 0.039～0.35?g and 0.037～0.33?g, respectively. The average recovery of emodin and chrysophanol and physcion was 97.4% and 98.0% and 97.1%, with RSD of 1.70% and 1.56% and 1.83%, respectively. Conclusion: The method can be used to the quality control of Jinzhitai Capsule.