Effect of lime water processing of Pinelliae Rhizoma Praeparatum on toxic component lectin protein / 中国中药杂志

The present study investigated the effect of immersion in the excipient lime water on the toxic component lectin protein and explained the scientific connotation of lime water detoxication during the processing of Pinelliae Rhizoma Praeparatum. Western blot was used to investigate the effects of immersion in lime water with different pH(pH 10, 11, and 12.4), saturated sodium hydroxide, and sodium bicarbonate solution on the content of lectin protein. The protein compositions of the supernatant and the precipitate after immersing lectin protein in lime water of different pH were determined by the SDS-PAGE method combined with the silver staining technique. The MALDI-TOF-MS/MS technique was used to detect the molecular weight distribution of peptide fragments in the supernatant and precipitate after immersing lectin protein in lime water of different pH, and circular dichroism spectroscopy was used to detect the ratio changes in the secondary structure of lectin protein during the immersion. The results showed that immersion in lime water at pH>12 and saturated sodium hydroxide solution could significantly reduce the content of lectin protein, while immersion in lime water at pH<12 and sodium bicarbonate solution had no significant effect on lectin protein content. The corresponding lectin protein bands and molecular ion peaks were not detected at the 12 kDa position in the supernatant and precipitate after immersing the lectin protein in lime water at pH>12, which was attributed to the fact that lime water immersion at pH>12 could significantly change the ratio of the secondary structure of lectin protein, resulting in irreversible denaturation, while lime water immersion at pH<12 did not change the ratio of the secondary structure of lectin protein. Therefore, pH>12 was the key condition for the detoxication of lime water during the processing of Pinelliae Rhizoma Praeparatum. Lime water immersion at pH>12 could cause irreversible denaturation of lectin protein, resulting in a significant decrease in the inflammatory toxicity of Pinelliae Rhizoma Praeparatum, which played a key role in detoxification.

Effect of Pinelliae Rhizoma processed with lime and licorice on toxic lectin protein / 中国中药杂志

The present study was aimed to investigate the effect of lime and licorice processing of Pinelliae Rhizoma on its toxic lectin protein and clarify the scientific detoxification connotation of lime and licorice processing of Pinelliae Rhizoma. Western blot was used to semi-quantitatively analyze the contents of lectin in Pinelliae Rhizoma and Pinelliae Rhizoma Praeparatum. Raw products and lectin were treated by soaking in licorice juice, lime solution or mixture solution of these two to investigate the different processing time on the content of toxic lectin protein. SDS-PAGE gel electrophoresis was used to analyze the changes of lectin protein bands in the solution and precipitates before and after processing. MALDI-TOF technology was used to qualitatively analyze and compare the protein molecular weight before and after processing. The results showed that the contents of lectin in Pinelliae Rhizoma and Pinelliae Rhizoma Praeparatum were 5.01% and 0.04% respectively, indicating that processing could significantly reduce the content of active lectin in raw products. The results also showed that the content of lectin in raw drugs decreased significantly after soaking in lime solution for one day or in licorice juice for three day, and the effect was greatest in mixture solution. Qualitative analysis showed that after being treated by soaking in lime solution, the lectin protein was decomposed into small peptide segments, while after being treated by soaking in licorice juice, the lectin protein was denatured and precipitated. The structure of lectin protein in Pinelliae Rhizoma was broken after being processed with licorice juice and lime solution, which significantly reduced the content of toxic lectinprotein. This is one of the detoxification mechanisms of Pinelliae Rhizoma processing.

Expression, purification and induction of apoptosis of gastric cancer cells by salvia miltiorrhiza lectin in vitro / 医学研究生学报

Objective　The active protein of traditional Chinese medicine has anti-tumor effect, and salvia miltiorrhiza is an important anti-tumor traditional Chinese medicine. Here, the effect of Salvia miltiorrhiza lectin protein (SMLP) on the apoptosis of gastric cancer cells was studied.　Methods　SMLP expressed and purified from prokaryotic cells was used to treat the gastric cancer cells SGC-7901. The experiment was divided into the control group (untreated) and the SMLP treatment group (final concentration of 10 μmol / L of SMLP was treated for 24 h). Real-time RT-PCR and Western blot were used to detect the changes of apoptosis gene expression. Flow cytometry and Hoechst staining were applied to detect the apoptotic status. Caspase-3 and Caspase-9 activity assay kits were used to detect the apoptotic level.　Results　The result of RT-PCR showed that the mRNA level of Bax in the SMLP treatment group was significantly higher than in the control group (1.00±0.12 vs 0.67±0.10）(P<0.05). After treatment with SMLP to gastric cancer cells, the activity and expression level of cleaved Caspase-3 and Caspase-9 were increased significantly compared with the control group (P<0.05). The cell nucleus in the control group was bigger and rounder, with smooth surface and uniform staining, whilst in the SMLP-treated group, the cell nucleus became deeper with pyknosis, representing typical morphological characteristics of apoptosis. The early apoptosis level in the control group was 6.55%, and the SMLP treatment group reached 10.18%, showing an increase in the level of apoptosis.　Conclusion　SMLP expressed and purified in vitro can promote the apoptosis of gastric cancer cells, which is of great significance for further revealing the function of plant lectin and investigating the anti-tumor effect on the protein of traditional Chinese medicine.