National Engineering Laboratory for Resource Developing of Endangered Chinese Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi, China.
Pharm Biol. 2013 Sep;51(9):1196-203. doi: 10.3109/13880209.2013.784342. Epub 2013 Jun 19.
Rabdosia rubescens (Hemsl.) Hara (Lamiaceae) is widely used in traditional Chinese medicines for the treatment of antitumor, antimicrobial, anti-inflammatory and antioxidation. It is also used as a supplement in the treatment of many cancers, such as esophagus, mammary gland, liver and prostate cancers.
To investigate the multidrug resistance (MDR) reversal effects and its possible mechanism of R. rubescens extracts on human breast cancer cell line MCF-7/Adr (Michigan Cancer Foundation--7/adriamycin resistance).
Rabdosia rubescens were extracted by reflux extraction method with different solvent such as petroleum ether, chloroform, ethyl acetate, n-butyl alcohol and water in order and obtain petroleum ether fraction (PEF), chloroform fraction (CF), ethyl acetate fraction (EAF), n-butyl alcohol fraction (BAF) and aqueous fraction (AF). The active extract fractions of R. rubescens were screened by rhodamine123 (Rh123) accumulation assay. Cytotoxicity of the effect fraction was examined by the MTT assay; the intracellular accumulation of adriamycin and expression of P-gp were examined by flow cytometry; the gene transcription of MDR1 was determined by RT-PCR.
CF and EAF fractions could increase the intracellular accumulation of adriamycin in MCF-7/Adr cells, PEF, BAF and AF fractions showed little effect on the intracellular accumulation of adriamycin or Rh123. When adriamycin was used in combination with CF and EAF fractions at non-toxic concentration on MCF-7/Adr cells, CF and EAF fractions can reverse MDR of MCF-7/Adr cells, and the reverse folds were 2.16 (CF, 4 μg/mL), 4.60 (CF, 20 μg/mL), 1.87 (EAF, 4 μg/mL) and 4.02 (EAF, 20 μg/mL), respectively. After treatment with CF (4.20 μg/mL) and EAF (4.20 μg/mL) for 48 h, the MDR1 gene expression level in MCF-7/Adr cells was decreased by 40.17, 48.14, 33.86 and 42.52%, and the abundance of P-gp also decreased by 8.63, 24.53, 27.50 and 34.91% in MCF-7/Adr cells, respectively.
These results indicate the therapeutic value of chloroform fraction (CF) and ethyl acetate fraction (EAF) from R. rubescens as potential MDR reversing agents and warranted further investigation.
罗勒（Hemsl.）哈（唇形科）被广泛应用于传统中药治疗抗肿瘤，抗菌，抗炎和抗氧化。它也被用作许多癌症的补充治疗，如食道，乳腺，肝和前列腺癌。
探讨罗勒提取物对人乳腺癌细胞 MCF-7/Adr（密歇根癌症基金会-7/阿霉素耐药）的多药耐药（MDR）逆转作用及其可能机制。
采用回流提取法，用不同溶剂（如石油醚、氯仿、乙酸乙酯、正丁醇和水）依次提取罗勒，得到石油醚部分（PEF）、氯仿部分（CF）、乙酸乙酯部分（EAF）、正丁醇部分（BAF）和水相部分（AF）。采用罗丹明 123（Rh123）蓄积试验筛选罗勒的活性提取部位。MTT 法检测有效部位的细胞毒性；采用流式细胞术检测阿霉素的细胞内蓄积和 P-gp 的表达；采用 RT-PCR 检测 MDR1 基因转录。
CF 和 EAF 部分可增加 MCF-7/Adr 细胞内阿霉素的蓄积，PEF、BAF 和 AF 部分对阿霉素或 Rh123 的蓄积影响不大。当阿霉素与 CF 和 EAF 部分在非毒性浓度下联合应用于 MCF-7/Adr 细胞时，CF 和 EAF 部分可逆转 MCF-7/Adr 细胞的 MDR，逆转倍数分别为 2.16（CF，4μg/ml）、4.60（CF，20μg/ml）、1.87（EAF，4μg/ml）和 4.02（EAF，20μg/ml）。用 CF（4.20μg/ml）和 EAF（4.20μg/ml）处理 48h 后，MCF-7/Adr 细胞中 MDR1 基因表达水平分别降低 40.17%、48.14%、33.86%和 42.52%，P-gp 的丰度也分别降低 8.63%、24.53%、27.50%和 34.91%。
这些结果表明罗勒氯仿部分（CF）和乙酸乙酯部分（EAF）具有作为潜在的 MDR 逆转剂的治疗价值，值得进一步研究。
