PP9, a steroidal saponin, induces G2/M arrest and apoptosis in human colorectal cancer cells by inhibiting the PI3K/Akt/GSK3ß pathway.

Colorectal cancer (CRC) represents one of the commonest malignancies around the world. PP9, a natural steroidal saponin, was firstly isolated from the rhizomes of Paris polyphylla var. latifolia. However, the therapeutic effects of PP9 on CRC and the underlying molecular mechanism remain undefined. Here, we demonstrated that treatment with PP9 time- and dose-dependently inhibited HT-29 and HCT116 cells without significantly inhibiting normal NCM460 cells. Furthermore, our results indicated that PP9 effectively induced G2/M phase arrest by upregulating p21 and suppressing cdc25C, Cyclin B1 and cdc2. Meanwhile, PP9 upregulated cleaved Caspase 3, cleaved Caspase 9 and cleaved PARP and Bax, while downregulating Bcl-2 to stimulate cell apoptosis. Mechanistically, PP9-suppressed PI3K/Akt/GSK3ß signaling, while the PI3K inhibitor LY294002 augmented PP9-mediated apoptosis, G2/M arrest and effects on PI3K/Akt/GSK3ß related proteins. Finally, we showed that PP9 (10 mg/kg) significantly reduced tumor growth in nude mouse CRC xenografts, more potently than 5-Fu (20 mg/kg). Jointly, these data firstly demonstrated that PP9 promotes G2/M arrest and apoptotic death in CRC cells through PI3K/Akt/GSK3ß signaling suppression, suggesting that PP9 could be considered a new and promising candidate for CRC therapy.

New Steroidal Saponins from the Rhizomes of Paris vietnamensis and Their Cytotoxicity.

Four new spirostanol saponins, named pavitnosides A-D (1-4), with six known steroidal saponins 5-10 were isolated from the rhizomes of Paris vietnamensis. Their chemical structures were determined based on extensive spectroscopic studies and chemical methods. The aglycones of pavitnoside B and pavitnoside C were not reported in previous work. The cytotoxicity of all saponins was evaluated against human glioblastoma U87MG and U251 cell lines. The new spirostanol saponin 1 displayed weak anti-proliferative activity against U87MG cell line and the known saponins 8 and 9 exhibited significant cytotoxicity against the two tumor cell lines, with IC50 values of 2.16 to 3.14 µM, but did not affect the growth of primary cultures of human astrocytes.

Metformin; a review of its history and future: from lilac to longevity.

Metformin is a widely prescribed medication that has been used to treat children with type 2 diabetes in the United States for the past 15 years. Metformin now has a variety of clinical applications in pediatrics, and its potential clinical uses continue to expand. In addition to reviewing the current understanding of its mechanisms of action including the newly discovered effects on the gastrointestinal tract, we will also discuss current clinical uses in pediatrics, including in type 1 diabetes. Finally, we examine the existing state of monitoring for metformin efficacy and side effects and discuss prospective future clinical uses.

Quantitative determination and evaluation of Paris polyphylla var. yunnanensis with different harvesting times using UPLC-UV-MS and FT-IR spectroscopy in combination with partial least squares discriminant analysis.

A rapid method was developed and validated by ultra-performance liquid chromatography-triple quadrupole mass spectroscopy with ultraviolet detection (UPLC-UV-MS) for simultaneous determination of paris saponin I, paris saponin II, paris saponin VI and paris saponin VII. Partial least squares discriminant analysis (PLS-DA) based on UPLC and Fourier transform infrared (FT-IR) spectroscopy was employed to evaluate Paris polyphylla var. yunnanensis (PPY) at different harvesting times. Quantitative determination implied that the various contents of bioactive compounds with different harvesting times may lead to different pharmacological effects; the average content of total saponins for PPY harvested at 8 years was higher than that from other samples. The PLS-DA of FT-IR spectra had a better performance than that of UPLC for discrimination of PPY from different harvesting times.

Inhibition of lung cancer in diethylnitrosamine-induced mice by Rhizoma paridis saponins.

Lung cancer is the foremost cause of cancer mortality and a growing economic burden worldwide. Rhizoma paridis saponins (RPS) have been reported to exhibit potential anti-tumor effects on many kinds of tumor models. The present study was designed to investigate the mechanism-based chemopreventive nature of RPS against DEN-induced lung carcinogenesis in Kunming mice. As a result, the treatment with RPS reduced the severity of pulmonary histopathology. The mechanism of its antitumor effect involved in (a) reducing oxidative stress injury through up-regulating activities of CAT and SOD; (b) down-regulating the levels of inflammatory factors, like TNF-α, IL6, COX-2, and PGE2; (c) activation of caspase-3 and up-regulating the pro-apoptotic protein Bax; (d) decreasing the expression of PCNA; (e) depressing the expression of cancer stem cells marker CD133; (f) suppressing aberrant expression of cytokeratin 8 and 18; and (g) inhibiting EGFR/ PI3 K/Akt, EGFR/Ras/Erk and NF-κB pathways. Taken together, RPS would be a potent agent inhibiting lung tumor in the future.

cAMP-PKA-CaMKII signaling pathway is involved in aggravated cardiotoxicity during Fuzi and Beimu Combination Treatment of Experimental Pulmonary Hypertension.

Aconiti Lateralis Radix Praeparata (Fuzi) and Fritillariae Thunbergii bulbus (Beimu) have been widely used clinically to treat cardiopulmonary related diseases in China. However, according to the classic rules of traditional Chinese medicine, Fuzi and Beimu should be prohibited to use as a combination for their incompatibility. Therefore, it is critical to elucidate the paradox on the use of Fuzi and Beimu combination therapy. Monocrotaline-induced pulmonary hypertension rats were treated with either Fuzi, Beimu, or their combination at different stages of PH. We demonstrated that at the early stage of PH, Fuzi and Beimu combination significantly improved lung function and reduced pulmonary histopathology. However, as the disease progressed, when Fuzi and Beimu combination were used at the late stage of PH, right ventricular chamber dilation was histologically apparent and myocardial apoptosis was significantly increased compared with each drug alone. Western-blotting results indicated that the main chemical ingredient of Beimu could down-regulate the protein phosphorylation levels of Akt and PDE4D, whereas the combination of Fuzi and Beimu could up-regulate PKA and CaMKII signaling pathways. Therefore, we concluded that Fuzi and Beimu combination potentially aggravated the heart injury due to the inhibition of PDK1/Akt/PDE4D axis and subsequent synergistic activation of ßAR-Gs-PKA/CaMKII signaling pathway.

Curcumin alleviated the toxic reaction of Rhizoma Paridis saponins in a 45-day subchronic toxicological assessment of rats.

Rhizoma Paridis saponins (RPS), as steroid saponins, are the main components in Paris polyphylla. Curcumin (diferuloylmethane) is the most important component in the spice turmeric. In our previous research, RPS exhibited side effects such as nausea, vomiting, diarrhea, and so forth. Combination with curcumin not only alleviated the toxicity and gastric stimulus induced by RPS, but also improved the quality life of mice bearing tumor cells and enhanced their anticancer effect. This study evaluated subchronic toxicity of 45th dietary of RPS and curcumin on histopathology, biochemistry, and antioxidant index. As a result, RPS-treatment caused a slight liver injury (the elevation of serum AST, alkaline phosphatase (AKP), alanine transaminase (ALT), and gamma glutamyl transpeptidase (γ-GT), histopathological changes in liver section), oxidative stress (the enhancement of reactive oxygen species (ROS), malondialdehyde (MDA), and 8-hydroxy-2-deoxyguanosine (8-OHdG), separation of thioredoxin (Trx) and thioredoxin-interacting protein (TXNIP), but enhancement of heme oxygenase-1 (HO-1), glutathione S-transferase (GST), and nuclear factor-regulated factor 2 (Nrf2)), and inflammation (up-regulation of cyclooxygenase-2 (COX-2), interleukin-1ß (IL-1ß), and nuclear factor kappaB (NF-κB)). However, these changes were alleviated through co-treatment with curcumin. In conclusion, our work provided useful data for further research and new drug exploration of RPS and curcumin. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1935-1943, 2016.