Grape seed proanthocyanidins extracts promote apolipoprotein A-I mRNA expression in HepG2 cells under experimental sugar and high-sugar conditions.

OBJECTIVES: In this study, we investigated the effect of grape seed proanthocyanidins extracts (GSPE), which have been proved to have anti-oxidative and anti-aging functions, on the expression of apoA-L at mRNA level of HepG2 cells in vitro under the experimental conditions of high-sugar and sugar. MATERIALS AND METHODS: Cell viability was measured by sulforhodamine B (SRB). The apoA-I mRNA expression was assayed by real-time fluorescence quantitative polymerase chain reaction. Firstly, HepG2 cells were incubated in 10% inactivated newborn calf serum in Dulbecco's Modified Eagle Medium (DMEM). Next, cells were incubated with high-sugar and sugar serum-free medium, and added different concentration of GSPE (2.5, 5 and 10 microg/ml) for more than 24 hours, and thereafter, investigated whether GSPE can promote more apoA-I expression in HepG2 cells under the experimental conditions of high-sugar and sugar. RESULTS: In this experiment, HepG2 cells were incubated with high-sugar and sugar serum-free medium, and HepG2 cells incubated with high-sugar medium produced less apoA-I at mRNA level. The difference was significant (p < 0.05). When HepG2 cells were incubated with GSPE at concentration of 20 microg/ml or above for about 4 hours, cell viability measured by SRB was lower than 50%. However, cell viability of HepG2 cells incubated with GSPE at concentration of 10 microg/ml or below was higher than 70%. Therefore, we chose the HepG2 cells incubated with GSPE concentration of 2.5, 5, 10 microg/ml to observe the effect of GSPE on the mRNA expression of apoA-I. After incubated with GSPE, the apoA-I expression of HepG2 cells were significantly elevated at mRNA level compared to that of high sugar control (p < 0.05). Moreover, this action of GSPE showed dose dependent, and the dose of 2.5 microg/ml was optimal. CONCLUSIONS: GSPE (concentration of higher than 20 microg/ml) could inhibit HepG2 cell survival, and in HepG2 cells, endogenous apoA-I was significantly suppressed following 24h of exposure to high concentrations of glucose. Meanwhile GSPE could promote expression of apoA-L dose dependently at mRNA level when its concentration was lower than 10 microg/ml.

[Studies on original plant of traditional Chinese drug "bai zhi" (radix Angelicae Dahuricae) and its closely related wild plants. I. Morphological and anatomical studies on "bai zhi" and closely related wild plants].

OBJECTIVE: To supplement morphological and anatomical data for confirming the original plant of traditional Chinese drug "Bai Zhi" (Radix Angelicae Dahuricae). METHOD: Morphologocal observation and anatomical study were made on 4 cultivated breeds and closely related wild plants of "Bai Zhi". RESULT: According to morphological and anatomical characteristics discovered in this paper, 7 samples noted above could be divided into 3 groups: 1. 4 breeds ("Chuan Bai Zhi", "Hang Bai Zhi", "Qi Bai Zhi" and "Yu Bai Zhi") and Angelica dahurica var. formosana; 2. A. dahurica; 3. A. porphyrocaulis. CONCLUSION: In the morphological and anatomical point of view, A. dahurica var. formosana is closer to traditional Chinese drug "Bai Zhi" than others.

[Study on common character of regulative molecular mechanism of Chinese drug bailong and hexamethylen bisacetamide in human cancer cell cycle and their oncogene and tumor suppressor gene expression].

OBJECTIVE: To investigate the common regulative effects of the Chinese drug Bailong and hexamethylen bisacetamide (HMBA) on expressions of oncogenes (c-H-ras and c-myc), and tumor suppressor genes (Rb, p53 and p21) of MGC80-3 in human cancer cell cycle. METHODS: Adopting RNA Northern Blot to survey the levels of gene expressions of MGC80-3 different phases cells treated with Bailong and HMBA respectively. RESULTS: In different phases of MGC80-3 cells treated with Bailong and differentiation inducer HMBA, expressions of oncogenes c-H-ras and c-myc were inhibited by over 50.0%, messenger kinase subspecies PKC-alpha gene is similar with the expression inhibition of oncogenes, except effect of Bailong on the G2 phase in cell cycle. Effect of Bailong differs greatly from HMBA in the expression of tumor suppression genes. The expression of Rb and p21 in cells treated by HMBA did not increase but were inhibited by 39.5% and 33.3% respectively in G1 phase. The level of Rb gene expression was decreased, too by 3.0% in S phase. Comparison with HMBA the expression of Rb and p21 genes were increased after treatment by Bailong in all cell cycle. But the effect of Bailong on the expression of p53 gene which was increased obviously by 125.0%-233.4% in majority phase of MGC80-3 cells is similar to HMBA. CONCLUSION: (1) The effect of Bailong on the regulation of oncogenes and tumor suppressor gene is similar to HMBA but the effect of Bailong is better than that of HMBA. (2) Molecular mechanism of the Bailong or HMBA on the proliferative inhibition and differentiation of MGC80-3 related to regulation of the Bailong and HMBA on the oncogenes and tumor suppressor genes in cell cycle of MGC80-3.

[Regulative effects of bailong and Hexamethylene bisacetamide on growth and phenotype of human gastric cancer cells in cell cycle].

OBJECTIVE: To investigate and compare the common effect of Bailong, a Chinese herbal preparation, and Hexamethylene bisacetamide (HMBA), a western cell differentiation inducer, on growth regulation and phenotype of human gastric cancer (MGC80-3) cells in different phases of cell cycle. METHODS: Synchronized MGC80-3 cells in monolayer cultures with nitrous oxide under high pressure were double blocked with overdosage of TdR in the 4 cellular phases (G1, S, G2 and M), and then collected and treated with Bailong and 5 mmol/L HMBA respectively. RESULTS: Both medicines could suppress the cell proliferation, soft agar cloning growth and microfilament assembling of different phases of cells, the effect on cells of G1 phase was the most significant one. CONCLUSION: Bailong and HMBA had significant common characteristics in inducing cell differentiation of MGC80-3 cells in different phases of cell cycle.

Co-regulative effects of the cAMP/PKA and DAG/PKC signal pathways on human gastric cancer cells during differentiation induced by traditional Chinese medicines.

AIM: To evaluate the role of cAMP/PKA and DAG/PKC pathways of MGc80-3 cells treated with a traditional Chinese medicine compound, bailong preparation (bailong). METHODS: cAMP level, DAG content and activities of PKA and PKC were measured in different groups: control; 1.8 g/L bailong; 1.8 g/L bailong + 20 mg/L PKA inhibitor; and 5 µmol/L PKC inhibitor. RESULTS: When MGc80-3 cells were treated with bailong for 3 h, cAMP level and PKA activity were 113% and 19.7% higher than those of the control, while DAG content and PKC activity were 47.0% and 64.2% lower than those of the control. When the PKC pathway was blocked by PKC inhibitor GF-109203 X, cAMP level and PKA activity were increased by 78.8% and 33.5% compared to inhibitor GF-109203 X, and cAMP level and PKA activity were increased by 78.8% and 33.5% compared to the control, while the DAG content and PKC activity were decreased by 40.3% and 56.3%. When MGc80-3 cells were treated with bailong and PKA inhibitor blocked PKA pathways at the same time, cAMP level and PKA activity were decreased by 46.0% and 28.9%. On the other hand, DAG content and PKC activity were increased by 50.7% and 51.6% compared to the bailong group. CONCLUSION: There is a relationship of cause and effect between differentiation of MGc80-3 cells and the signal pathways. The results of this study are similar to that of hexamethylenebisacetamide (HMBA), suggesting that the two signal systems are the foundation of proliferative regulation of MGc80-3 cells treated with Chinese medicine bailong or HMBA.

Effects of K salt or a potassium blocker on gossypol-related hypokalemia.

Gossypol was found to be an effective male contraceptive. The most serious side effect of gossypol contraception was the presumed lowering of serum potassium levels. The purpose of this present randomized and controlled study was to evaluate the merit of ingesting K salt or a potassium blocker while using gossypol. Results indicated that supplementation of K salt does not cause a reversal of the effect of gossypol on serum potassium levels and the blocker triamterene does not prevent loss of serum potassium.