Chemical constituents from Paris rugosa rhizomes and their antimicrobial activities / 中国中药杂志

Paris rugosa(Melanthiaceae) only grows in Yunnan province of China at present, and its chemical constituents have not been systematically studied. In this study, nine compounds, including one new compound pariposide G(1) and eight known compounds of cerin(2), stigmast-4-en-3-one(3), β-ecdysone(4), ophiopogonin C'(5), methyl protogracillin(6), gracillin(7), parissaponin H(8), and parisyunnanoside G(9), were isolated and identified from the ethanol extract of P. rugosa rhizomes by column chromatography methods and semi-preparative high-performance liquid chromatography(HPLC). Compounds 1-9 were isolated from this plant for the first time. The antibacterial and antifungal activities of all the compounds were evaluated. The results showed that ophiopogonin C' had strong inhibitory effects on Candida albicans [MIC_(90)=(4.68±0.01) μmol·L~(-1)] and the fluconazole-resistant strain of C. albicans [MIC_(90)=(4.66±0.02) μmol·L~(-1)].

Mechanism of Paris Forrestii (Takht.) H. Li-Suppressing the Proliferation of Acute Myeloid Leukemia Cell Lines / 中国实验血液学杂志

OBJECTIVE@#To investigate the mechanism of Paris forrestii (Takht.) H. Li (PCT3)-suppressing the proliferation of HL-60, K562, KG-1 and HT-93 cells.@*METHODS@#cute myeloid leukemia cell lines such as HL-60, K562, KG-1 and HT-93 were treated with Paris forrestii (Takht.) H. Li (PCT3) for 24, 48, and 72 h, and MTT assay was employed to determine the cells proliferation. Meanwhile, the apoptosis of K562, HL-60, KG-1 and HT-93 cells were detected by flow cytometry after PCT3 (Control, 4 μg/ml, 8 μg/ml) treated for 24 h and the Western blot was performed to detect the expression of PARP,Caspase-3, MCL-1, BAX, BCL-2, P53, and P27. GAPDH was used as an internal loading control.@*RESULTS@#MTT assay showed that Paris forrestii (Takht.) H. Li (PCT3) significantly inhibited the proliferation of HL-60, K562, KG-1 and HT-93 cells in concentration and time-dependent manners. Compared with the control group, the leukemia cell viabilities were significantly suppressed (r =0.9436; r =0.8623; r =0.9922; r =0.8918). Paris forrestii (Takht.) H. Li (PCT3) induced apoptosis of leukemia cells in a concentration dependent manner, compared with the control group (P＜0.05 or P＜0.01). Western blot revealed that PARP, a major enzyme in DNA damage repair, and Caspase-3 another one of the major executive apoptotic enzymes were cleaved in cell lines examined, and this cleavage was concentration dependent. Anti-apoptotic proteins such as MCL-1 and BCL-2 were down regulated by Paris forrestii (Takht.) H. Li (PCT3), and Pro-apoptotic protein BAX was upregulated. And the protein of tumor suppressor gene P53 and its downstream signaling protein P27 increased.@*CONCLUSION@#Paris forrestii (Takht.) H. Li (PCT3) can inhibit the proliferation of leukemia cells by activating endogenous apoptosis pathway, and provide a potential new drug selection for clinical treatment of AML leukemia.

Saponins from Paris forrestii(Takht.)H.Li displays potent activity against acute myeloid leukemia by suppressing RNF6/AKT/mTOR signaling pathway / 中国药理学与毒理学杂志

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by the accu-mulation of immature myeloid progenitor cells in the bone marrow,compromising of normal hematopoi-esis and ultimately resulting in bone marrow failure. Chemotherapy is the mainstay treatment for all AML patients,however,drug resistance and clinical relapse limits its efficacy.The 5-year survival rate of AML patients is only 26.6%.Survival rates are even lower among patients ages 65 to 74 years (5.3%)and 75 years or older(1.6%).Therefore,exploring novel therapeutic agents is urgent for improving the outcome of patients with AML. Saponins are amphipathic glycosides found in traditional Chinese medicines. In the present study, we isolated a panel of saponins from Paris forrestii (Takht.) H. Li, a unique plant found in Tibet and Yunnan provinces, China. By examining their activities in suppressing acute myeloid leukemia cell proliferation, total saponins from Paris forrestii (TSPf) displayed more potent activity than individual ones.TSPf induced more than 40% AML cell apoptosis within 24 h and decreased the viability of all leukemia cell lines. TSPf-induced apoptosis was confirmed by both Annexin V staining and caspase-3 activation.TSPf downregulated pro-survival proteins Mcl-1,Bcl-xL and Bcl-2,but upreg-ulated the expression of tumor suppressor proteins p53,p27,Bax and Beclin 1.The AKT/mTOR signaling pathway is frequently over activated in various AML cells,and TSPf was found to suppress the activa-tion of both AKT and mTOR,but had no effects on their total protein expression.This was further con-firmed by the inactivation of 4EBP-1 and p70S6K,two typical downstream signal molecules in the AKT/mTOR pathway. More specifically, TSPf-inactivated AKT/mTOR signaling was found to be associated with downregulated RNF6, a recently identified oncogene in AML. RNF6 activated AKT/mTOR, and consistently, knockdown of RNF6 led to inactivation of the AKT/mTOR pathway. Furthermore, TSPf suppressed the growth of AML xenografts in nude mice models. Oral administration of 100 mg·kg-1 body weight almost fully suppressed tumor growth within 14 d, without gross toxicity. This study thus demonstrated that TSPf displays potent anti-AML activity by suppressing the RNF6/AKT/mTOR pathway. Given its low toxicity,TSPf could be developed for the treatment of AML.

Medicinal values and their chemical bases of Paris / 中国中药杂志

Medicinal values and their chemical bases of Paris (Trilliaceae) are reviewed. Paris plants include 40 species and varieties. Among them, 18 ones are medicinal plants with similarity in traditional uses. Fourteen species have been studied phytochemically, which led to isolation of 207 compounds including 121 steroidal saponins. These saponins are major active constituents from Paris plants, which can explain the traditional uses of the plants to treat cancer, malignant boil, bleeding, gastritis, and so on. The similarity in medicinal uses and chemical constituents of Paris plants implies the possibility of resource substitution among these species. It is worth to further investigate Paris plants in chemical constituents, pharmacological activity, biological property, and toxicology.