Acute and 13 weeks subchronic toxicological evaluation of the flavonoid-rich extract of Sophora flavescens.

The roots of Sophora flavescens have a long history of use in Chinese medicine for the treatment of various medical conditions. Flavonoids from the ethyl acetate extract of S. flavescens have shown anti-inflammatory, anticancer, and antidiabetic properties. The objective of this study was to evaluate the toxicological profile of a flavonoid-rich extract of S. flavescens (SFEA). We conducted acute and sub-chronic oral toxicity studies of SFEA in Kunming (KM) mice and Sprague-Dawley (SD) rats. Acute oral administration of 9.0 g/kg SFEA did not result in mortality, clinical signs of toxicity, or abnormal changes in the body weight or food consumption patterns. No significant changes in hematological, blood biochemical, or histopathological parameters were observed. A 13-week sub-chronic toxicity study was conducted in SD rats; the rats were orally administrated with various doses of SFEA (in mg/kg): 0 (control), 40, 80, 400, 800, and 1200. Mortality, clinical signs, or treatment-related changes in body weight, food consumption, hematological parameters, blood biochemical parameters, organ weights, or histopathological parameters were not observed. We found that SFEA is practically nontoxic to KM mice at a dose of 9.0 g/kg and that the no-observed-adverse-effect-level (NOAEL) of SFEA in SD rats is greater than 1200 mg/kg.

A Novel Flavonoid Kushenol Z from Sophora flavescens Mediates mTOR Pathway by Inhibiting Phosphodiesterase and Akt Activity to Induce Apoptosis in Non-Small-Cell Lung Cancer Cells.

The roots of Sophora flavescens (SF) are clinically used as a traditional Chinese medicine for the treatment of various lung diseases. In this study, we investigated the mechanism by which SF inhibits proliferation and induces apoptosis in non-small-cell lung cancer (NSCLC) cells. A new compound, kushenol Z (KZ), and 14 known flavonoids were isolated from SF. KZ, sophoraflavanone G, and kushenol A demonstrated potent cytotoxicity against NSCLC cells in a dose- and time-dependent manner; KZ showed a wide therapeutic window. We also found that KZ induced NSCLC cell apoptosis by increasing the Bax/Bcl-2 ratio and by activating caspase-3 and caspase-9 leading to mitochondrial apoptosis, and upregulated CHOP and activatedcaspase-7 and caspase-12, which triggered the endoplasmic reticulum stress pathway. After KZ treatment, we observed cAMP accumulation, which reflected the inhibition of cAMP-phosphodiesterase (PDE), along with the increase in PKA activity; additionally, phospho-p70 S6 kinase was downregulated. KZ also attenuated the phosphorylation of Akt and PRAS40, which was partially rescued by an Akt activator. This suggested that KZ mediated the antiproliferative activity in NSCLC cells by inhibiting the mTOR pathway through the inhibition of cAMP-PDE and Akt. These findings suggested that KZ may be used as a promising cAMP-PDE and Akt inhibitor in targeted chemotherapeutic drug development.

Doliroside A from Dolichos falcata Klein suppressing amyloid ß-protein 42 fibrillogenesis: An insight at molecular level.

A bioactive chemical constituent, doliroside A, from Chinese traditional herbal medicine Dolichos falcata Klein was isolated, purified and identified by 60% ethanol extraction, thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) spectroscopy. Molecular interaction mechanism between doliroside and amyloid ß42 protein was evaluated by thioflavin T fluorescence (ThT), circular dichroism (CD), atomic force microscope (AFM), and differential scanning calorimeter (DSC) from the aspects of kinetics, secondary structure, morphology, and thermodynamics, respectively. Results show that the purity of doliroside A is 99.9% by HPLC, and its chemical structure is identified by 1H- and 13C-NMR. Doliroside A is observed to be concentration-dependent inhibiting the fibrillation of Aß42 with the IC50 value of 26.57 ± 1.6 µM. CD and DSC results imply that doliroside A can bind to the nuclei and oligomers of Aß42 to form a stable complex and suppress Aß42 fibrillation. AFM images show that doliroside A, after bound to the nuclei and oligomers, redirect Aß42 into off-pathway, amorphous oligomers. These findings not only provide a full insight into the molecular interaction mechanisms between Aß42 and doliroside A, but also facilitate the development of new native anti-AD drug of doliroside A compound.

Safety assessment of saponins extract in Dolichos falcatus Klein: Subchronic study in Sprague-Dawley rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Dolichos falcatus Klein (DF), a Chinese Dai ethnic medicine popularly known as "Tuoyeteng" in Yunnan province of China, has been widely used in China to treat fracture, rheumatoid arthritis and soft tissue injuries for a long time. Our previous study showed that saponins in DF (DFS) ameliorated the gouty arthritis induced by MSU crystals in vivo and in vitro. The present study was carried out to evaluate the no-observed-adverse-effect level (NOAEL) of DFS. MATERIALS AND METHODS: Sprague-Dawley rats (10/sex/group) were gavaged with DFS at dose level of 0, 50, 100 and 200 mg/kg body weight /day for 90-days. RESULTS: DFS administration did not result in mortality or show treatment-related changes in clinical signs of toxicity, body weights gain or feed consumption. Similarly, in addition to slightly hemolytic anemia and gastrointestinal tract lesion in males of high-dose treatment group, no toxicologically significant treatment-related changes in hematological, clinical chemistry, urine analysis parameters, organ weights, and macroscopic and microscopic abnormalities were noted during the testing period. CONCLUSION: The results of subchronic toxicity study support the NOAEL for DFS as 200 mg/kg/d in females and as 100mg/kg/d in males. These results provide an important reference for further DFS-related clinical trials or new drug exploration.

HPLC-based activity profiling of anti-hepatocellular carcinoma constituents from the Tibetan medicine, Caragana tibetica.

During the screening of a traditional Chinese folk herb library against HepG2 and Hep3B cell lines, the EtOAc extract from the Tibetan medicine, Caragana tibetica (CT-EtOAc) exhibited potential anti-hepatocellular carcinoma (anti-HCC) activity. HPLC-based activity profiling was performed for targeted identification of anti-HCC activity from CT-EtOAc by MS-directed purification method. CT-EtOAc was separated by time-based fractionation for further anti-HCC bioassay by a semipreparative HPLC column (150 mm × 10 mm i.d., 5 µm) with a single injection of 5 mg. Bioassay-guided and ESIMS-directed large scale purification was performed with a single injection of 400 mg of CT-EtOAc by peak-based fractionation. A 1.4-mm heavy wall micro NMR tube with z-gradient was used to measure one and two dimensional NMR spectra for the minor or trace amounts of components of the extract. Two active compounds could be elucidated as naringenin chalcone (CT-1) and 3-hydroxy-8, 9-dimethoxypterocarpan (CT-2) relevant to anti-HCC effects for the EtOAc extract of C. tibetica rapidly and unambiguously by this protocol.

Dolichos falcata Klein attenuated the inflammation induced by monosodium urate crystals in vivo and in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Dolichos falcata Klein (DF), a Chinese Dai ethnic medicine popularly known as "Tuoyeteng" in Yunnan province of China, has been widely used as a traditional herbal medicine for the treatment of fracture and beriberoid disease for a long time in China. The present study was carried out to investigate the anti-inflammatory activity and the bioactive chemical constituents of DF, and further to assess its possible mechanism on gouty arthritis in an animal model of the MSU crystals-induced gouty inflammation. MATERIALS AND METHODS: The ethanol extract (EE) of DF at the doses of 10, 20 and 40 mg/kg was administered to the rats treated with MSU crystals to evaluate the anti-gouty arthritis effect. Subsequently, the components of EE were isolated and identified using classical methods. Phyto-chemical analysis of EE was further carried out by HPLC-DAD. Finally, the anti-inflammatory effect of EE and two isolated components were assessed using the MSU crystals-treated monocyte/macrophage cell line RAW 264.7 in vitro. RESULTS: EE (10, 20 and 40 mg/kg) significantly attenuated the pain threshold value, the joint swelling degree, the inflammatory cell infiltration of articular tissue and the increased levels of pro-inflammatory cytokines in MSU crystals-treated rats. Moreover, doliroside A (DA) and medicagenic acid-3-O-ß-D-glucopyranoside (MG) were isolated and identified from EE. The major components of EE, including DA, MG and other triterpenoids, were well confirmed by HPLC. A further study revealed that EE, DA and MG (10, 20, 40µg/mL) exhibited stronger inhibitory effects on the production of pro-inflammatory cytokines (including interleukin-1ß, interleukin-6 and tumor necrosis factor-α) in MSU crystals-treated RAW 264.7 cells. CONCLUSION: These findings indicate that the major triterpenoids present in DF have a remarkable effect on improving symptoms of acute gouty arthritis induced by MSU crystals through inhibiting the production of pro-inflammatory cytokines.

Polydatin ameliorates renal injury by attenuating oxidative stress-related inflammatory responses in fructose-induced urate nephropathic mice.

A series of studies have recently demonstrated that the oxidative stress, nuclear factor-kappa B (NF-κB) activation and the subsequent coordinated inflammatory responses played an important role in the pathogenesis of urate nephropathy (UN). Polydatin has been suggested to have the properties of anti-oxidative, anti-inflammatory and nephroprotective effects. However, the possible protective and beneficial effects of polydatin on UN are not fully elucidated. Therefore, we investigated the potential beneficial effects and possible mechanisms of polydatin on UN. In this study, polydatin showed inhibitory activities on xanthine oxidase to repress the level of serum uric acid in vivo and in vitro. Further investigations revealed that polydatin displayed little toxic effects and significantly ameliorated the renal function in fructose-induced UN mice. The nephroprotective activities of polydatin was not only due to the effects on remarkably attenuating the oxidative stress induced by uric acid, but also on markedly suppressing the oxidative stress-related inflammatory cascade, including decreasing the expressions of NF-κB p65, COX-2 and iNOS proteins and inhibiting the productions of TNF-α, PGE(2) and IL-1ß. These findings elucidated that polydatin exhibited prominent nephroprotective activities and low toxic effects.