The synchronized feature of Saururus chinensis and gut microbiota against T2DM, NAFLD, obesity and hypertension via integrated pharmacology.

Type 2 diabetes mellitus (T2DM), nonalcoholic fatty liver disease (NAFLD), obesity (OB) and hypertension (HT) are categorized as metabolic disorders (MDs), which develop independently without distinct borders. Herein, we examined the gut microbiota (GM) and Saururus chinensis (SC) to confirm their therapeutic effects via integrated pharmacology. The overlapping targets from the four diseases were determined to be key protein coding genes. The protein-protein interaction (PPI) networks, and the SC, GM, signalling pathway, target and metabolite (SGSTM) networks were analysed via RPackage. Additionally, molecular docking tests (MDTs) and density functional theory (DFT) analysis were conducted to determine the affinity and stability of the conformer(s). TNF was the main target in the PPI analysis, and equol derived from Lactobacillus paracasei JS1 was the most effective agent for the formation of the TNF complex. The SC agonism (PPAR signalling pathway), and antagonism (neurotrophin signalling pathway) by SC were identified as agonistic bioactives (aromadendrane, stigmasta-5,22-dien-3-ol, 3,6,6-trimethyl-3,4,5,7,8,9-hexahydro-1H-2-benzoxepine, 4α-5α-epoxycholestane and kinic acid), and antagonistic bioactives (STK734327 and piclamilast), respectively, via MDT. Finally, STK734327-MAPK1 was the most favourable conformer according to DFT. Overall, the seven bioactives from SC and equol that can be produced by Lactobacillus paracasei JS1 can exert synergistic effects on these four diseases.

Saururus chinensis (Lour.) Baill. extract promotes skeletal muscle cell differentiation by positively regulating mitochondrial biogenesis and AKT/mTOR signaling in vitro.

Promotion of myoblast differentiation by activating mitochondrial biogenesis and protein synthesis signaling pathways provides a potential alternative strategy to balance energy and overcome muscle loss and muscle disorders. Saururus chinensis (Lour.) Baill. extract (SCE) has been used extensively as a traditional herbal medicine and has several physiological activities, including anti­asthmatic, anti­oxidant, anti­inflammatory, anti­atopic, anticancer and hepatoprotective properties. However, the effects and mechanisms of action of SCE on muscle differentiation have not yet been clarified. In the present study, it was investigated whether SCE affects skeletal muscle cell differentiation through the regulation of mitochondrial biogenesis and protein synthesis in murine C2C12 myoblasts. The XTT colorimetric assay was used to determine cell viability, and myosin heavy chain (MyHC) levels were determined using immunocytochemistry. SCE was applied to C2C12 myotube at different concentrations (1, 5, or 10 ng/ml) and times (1,3, or 5 days). Reverse transcription­quantitative PCR and western blotting were used to analyze the mRNA and protein expression change of factors related to differentiation, mitochondrial biogenesis and protein synthesis. Treatment of C2C12 cells with SCE at 1,5, and 10 ng/ml did not affect cell viability. SCE promoted C2C12 myotube formation and significantly increased MyHC expression in a concentration­ and time­dependent manner. SCE significantly increased the mRNA and protein expression of muscle differentiation­specific markers, such as MyHC, myogenic differentiation 1, myogenin, Myogenic Factor 5, and ß­catenin, mitochondrial biosynthesis­related factors, such as peroxisome proliferator­activated receptor­gamma coactivator­1α, nuclear respirator factor­1, AMP­activated protein kinase phosphorylation, and histone deacetylase 5 and AKT/mTOR signaling factors related to protein synthesis. SCE may prevent skeletal muscle dysfunction by enhancing myoblast differentiation through the promotion of mitochondrial biogenesis and protein synthesis.

Cytotoxic effects of neolignans from Saururus cernuus (Saururaceae) against prostate cancer cells.

In this study, five neolignans were isolated from Saururus cernuus-threo-dihydroguaiaretic acid (1), threo-austrobailignan-6 (2), threo-austrobailignan-5 (3), verrucosin (4), and saucernetin (5)-and have their cytotoxic effects evaluated in prostate cancer cell lines (PC3 and DU145). Initially, using an in silico approach, tested compounds were predicted to be absorbed by the gastrointestinal tract, be able to permeate the blood-brain barrier and did not show any alert in PAINS (pan-assay structures interference). In vitro assays showed that compounds 2, 4, and 5 reduced cell viability of DU145 cell line at 100 µmol/L after 48 h while compounds 1 and 3 showed to be inactive at the same conditions. Furthermore, compounds 4 and 5 reduced cell number as early as in 24 h at 50 µmol/L and compound 2 showed effects at 100 µmol/L in 24 h against both cancer cell lines PC3 and DU145. Studies using flow cytometry were conducted and indicated that compound 4 induced strong necrosis and apoptosis whereas compound 5 induced strong necrosis. Otherwise, less active compound 2 did not show evidence of induction of apoptosis or necrosis, suggesting that its mechanism of action involves inhibition of cell proliferation. In conclusion, compounds 4 and 5 have been shown to be promising cytotoxic agents against prostate cancer cell lines and can be used as a starting point for the development of new drugs for the treatment of prostate cancer.

Neolignans isolated from Saururus cernuus L. (Saururaceae) exhibit efficacy against Schistosoma mansoni.

Schistosomiasis, a parasitic disease caused by the blood fluke of the genus Schistosoma, affects over 230 million people, especially in developing countries. Despite the significant economic and public health consequences, only one drug is currently available for treatment of schistosomiasis, praziquantel. Thus, there is an urgent demand for new anthelmintic agents. Based on our continuous studies involving the chemical prospection of floristic biodiversity aiming to discover new bioactive compounds, this work reports the in vitro antiparasitic activity against Schistosoma mansoni adult worms of neolignans threo-austrobailignan-6 and verrucosin, both isolated from Saururus cernuus L. (Saururaceae). These neolignans showed a significant in vitro schistosomicidal activity, with EC50 values of 12.6-28.1 µM. Further analysis revealed a pronounced reduction in the number of S. mansoni eggs. Scanning electron microscopy analysis revealed morphological alterations when schistosomes were exposed to either threo-austrobailignan-6 or verrucosin. These relevant antischistosomal properties were accompanied by low cytotoxicity potential against the animal (Vero) and human (HaCaT) cell lines, resulting in a high selectivity index. Considering the promising chemical and biological properties of threo-austrobailignan-6 and verrucosin, this research should be of interest to those in the area of neglected diseases and in particular antischistosomal drug discovery.

Comparative pharmacokinetic study of six lignans in normal and diabetic rats after oral administration of Saururus chinensis extract by LC-MS/MS.

Saururus chinensis (SC) possesses significant anti-diabetic activity and lignans were its major bioactive compounds. In this study, a rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was established for simultaneous quantification of six lignans, namely (-)-(7R,8R)-machilin D (1), verrucesin (2), rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan (3), manassantin A (4), manassantin B (5), and saucerneol F (6) in rat's plasma. It was validated with acceptable linearity (r ≥ 0.9922), accuracy (80.42-95.17%), precision (RSD ≤ 12.08%), and extraction recovery (80.36-93.45%). The method was successfully applied to the comparative pharmacokinetic study of the six lignans in normal and diabetic rats after oral administration of SC extract. Results showed that the areas under the plasma concentration-time curve (AUC0 → t and AUC0 → ∞ ) of (-)-(7R,8R)-machilin D, rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan, manassantin B, and saucerneol F in diabetic rats were significantly increased, and the plasma clearance (CL) of (-)-(7R,8R)-machilin D in diabetic rats was significantly decreased. However, the AUC0 → t and AUC0 → ∞ of verrucesin were significantly decreased, and its CL was significantly increased in diabetic rats compared with those in normal rats. These results indicated that there were remarkable differences in the pharmacokinetic parameters between the normal and diabetic rats. The pharmacokinetic studies might be beneficial for the clinical use of SC as hypoglycemic agent.

Machilin D, a Lignin Derived from Saururus chinensis, Suppresses Breast Cancer Stem Cells and Inhibits NF-κB Signaling.

Cancer stem cells are responsible for breast cancer initiation, metastasis, and relapse. Targeting breast cancer stem cells (BCSCs) using phytochemicals is a good strategy for the treatment of cancer. A silica gel, a reversed-phase C18 column (ODS), a Sephadex LH-20 gel, thin layer chromatography, and high-performance liquid chromatography (HPLC) were used for compound isolation from Saururus chinensis extracts. The isolated compound was identified as machilin D by mass spectrometry and nuclear magnetic resonance (NMR). Machilin D inhibited the growth and mammosphere formation of breast cancer cells and inhibited tumor growth in a xenograft mouse model. Machilin D reduced the proportions of CD44+/CD24- and aldehyde dehydrogenase 1 (ALDH1)-positive cells. Furthermore, this compound reduced the nuclear localization of the NF-κB protein and decreased the IL-6 and IL-8 secretion in mammospheres. These results suggest that machilin D blocks IL-6 and IL-8 signaling and induces CSC death and thus may be a potential agent targeting BCSCs.

A Review of Traditional Uses, Phytochemistry, and Pharmacological Properties of the Genus Saururus.

The genus Saururus, belonging to Saururaceae, contains two species, S. cernuus L. and S. chinensis (Lour) Baill. with common utilization in traditional medicine from Asia to North America for the treatment of edema, beriberi, jaundice, leucorrhea, urinary tract infections, hypertension, hepatitis diseases, and tumors. An extensive review of literature was made on traditional uses, phytochemistry, and ethnopharmacology of Saururus using ethno-botanical books, published articles, and electronic databases. The 147 of chemical constituents have been isolated and identified from S. cernuus and S. chinensis, and lignans, flavonoids, alkaloids, anthraquinones, saponins, and phenols are the major constituents. Various pharmacological investigations in many in vitro and in vivo models have revealed the potential of the genus Saururus with anti-inflammatory, antitumor, anti-oxidant, hepatoprotective, antimelanogenic, lipid-lowering, and bone protective activities, supporting the rationale behind numerous of its traditional uses. Due to the noteworthy pharmacological properties, Saururus can be a better option for new drug discovery. Data regarding many aspects of this plant such as toxicology, pharmacokinetics, quality-control measures, and the clinical value of the active compounds is still limited which call for additional studies.

Two new lignans from Gymnotheca involucrata.

A new dibenzocyclooctdiene (1), and a new eupodienone (2) type lignans were isolated along with five known analogues from the whole plant of Gymnotheca involucrata Pei. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis. Bioassay results showed that compounds 1 and 2 exhibited no antimicrobial activity against four Gram-positive bacterial strains and four Gram-negative bacteria at the concentration of 1 mg/mL.

Two new lignans from the aerial parts of Saururus chinensis with cytotoxicity toward nasopharyngeal carcinoma.

Two new lignans (1 and 12), together with 15 known compounds (2-11 and 13-17), were isolated from the aerial parts of Saururus chinensis Baill. Their structures were determined through extensive spectroscopic analyses. All the isolates were evaluated for their cytotoxicity against four human nasopharyngeal carcinoma cells (HONE1, CNE1, CNE2, and SUNE1). Compound 13 showed the most potent cytotoxicity toward HONE1, SUNE1, CNE2, and CNE1 cells with IC50 values of 0.76, 5.42, 5.86 and 6.28 µM, respectively. Further studies revealed that compound 13 suppressed cell growth by arresting the cell cycle at the S phase and induced cell apoptosis in the HONE1 cell line.

Antileishmanial activity and ultrastructural changes of related tetrahydrofuran dineolignans isolated from Saururus cernuus L. (Saururaceae).

OBJECTIVE: This work describes the isolation of anti-Leishmania amazonensis metabolites from Saururus cernuus (Saururaceae). Additionally, ultrastructural changes in promastigotes were evidenced by electron microscopy. METHODS: The MeOH extract from the leaves of S. cernuus was subjected to bioactivity-guided fractionation. Anti-L. amazonensis activity of purified compounds was performed in vitro against promastigote and amastigote forms. KEY FINDINGS: Bioactivity-guided fractionation of the MeOH extract from the leaves of S. cernuus afforded two related tetrahydrofuran dineolignans: threo,threo-manassantin A (1) and threo,erythro-manassantin A (2). Compounds 1 and 2 displayed activity against promastigotes (EC50 of 35.4 ± 7.7 and 17.6 ± 4.2 µm, respectively) and amastigotes (EC50 of 20.4 ± 1.9 and 16.0 ± 1.1 µm, respectively), superior to that determined for the positive control miltefosine (EC50 of 28.7 ± 3.5 µm). Reduced cytotoxicity for host cells was observed for both compounds. Additionally, ultrastructural changes in promastigotes leading to an alteration of structural morphology were observed, as evidenced by electron microscopy. Furthermore, these compounds altered the morphology and physiology of the plasmatic membrane of L. amazonensis. CONCLUSIONS: The obtained results indicated that dineolignans 1 and 2 could be considered as a scaffold for the design of novel and selective drug candidates for the treatment of leishmaniasis.

Lignans from Saururus chinensis with Inhibitory Effects on Nitric Oxide Production.

Three biogenetically related ent-sauchinone-type lignans (1-3), four 8-O-4'-type neolignans (4-7), a diaryldimethylbutane lignan (8), and a cyclic carbonate (9), along with 12 known compounds, have been isolated from a methanol extract of the aerial parts of Saururus chinensis. The structures of the new compounds (1-9) were determined by analysis of their 1D and 2D NMR spectra, HRESIMS, and ECD data. A putative biosynthetic pathway for the three ent-sauchinone-type lignans (1-3) was postulated. Compounds 1, 7, and 10 showed inhibitory effects on LPS-induced NO production in RAW 264.7 cells with IC50 values of 5.6, 8.6, and 9.2 µM, respectively.

Dibenzylbutane neolignans from Saururus cernuus L. (Saururaceae) displayed anti-Trypanosoma cruzi activity via alterations in the mitochondrial membrane potential.

The MeOH extract from leaves of Saururus cernuus L. (Saururaceae) displayed in vitro activity against trypomastigote forms of T. cruzi (100% of parasite death at 200 µg/mL), suggesting the presence of bioactive compounds. Thus, the bioactivity-guided fractionation was carried out, leading to the isolation of three related neolignan derivatives, identified as threo-austrobailignan-5 (1), threo-austrobailignan-6 (2), and threo-dihydroguaiaretic acid (3). Anti-T. cruzi activity of compounds 1-3 was performed against cell-derived trypomastigotes and intracellular amastigotes. Additionally, the mammalian cytotoxicity was investigated using NCTC cells. Compound 2 was the most effective against extracellular trypomastigotes with IC50 of 3.7 µM, while compound 3 showed activity in both clinically relevant forms of the parasite, trypomastigotes and amastigotes, with IC50 values of 7.0 and 16.2 µM, respectively. However, the structurally related compound 1 was inactive. Based on these results, compounds 2 and 3 were selected to evaluate the mechanism of cellular death. Compound 2 induced alteration in the plasma membrane permeability and consequently in the ROS levels after 120 min of incubation. By using flow cytometry and fluorescence microscopy, compound 3 showed alterations in the mitochondrial membrane potential (ΔΨm) of trypomastigotes. Considering the promising chemical and biological properties of neolignans 2 and 3, these compounds could be used as starting points to develop new lead compounds for Chagas disease.

Lignans from Saururus chinensis exhibit anti-inflammatory activity by influencing the Nrf2/HO-1 activation pathway.

As part of our ongoing program to develop anti-inflammatory agents, an extract derived from Saururus chinensis collected in Korea was found to inhibit nitric oxide (NO) production in RAW264.7 cells. Bioassay-guided fractionation led to the isolation two new (1 and 2) and six known dineolignans (3-8). To the best of our knowledge, manassatin B1 (3) was isolated from S. chinensis for the first time. All structures were elucidated using extensive spectroscopic analysis. Of these compounds, 2 and 8 inhibited lipopolysaccharide (LPS)-induced production of NO and showed IC50 values of 5.80 and 1.52 µM, respectively. LPS-induced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) was also significantly suppressed by the administration of 2 and 8. In addition, these lignans induced the expression of heme oxygenase-1 (HO-1) in a concentration-dependent manner. Nuclear translocation of nuclear-E2-related factor 2 (Nrf2), a key regulator of HO-1 protein expression, was also induced in RAW264.7 cells treated with 2 and 8. These findings suggested that these lignans exerted anti-inflammatory effects in RAW264.7 cells through modulation of the Nrf2/HO-1 pathway and that they were potential HO-1 inducers for preventing or treating inflammation.

Effect of Saururus chinensis leaves extract on type II collagen-induced arthritis mouse model.

BACKGROUND: Saururus chinensis leaves have been used as traditional medicine in Korea for pain, intoxication, edema, and furuncle. According to previous reports, these leaves exert renoprotective, neuroprotective, and antioxidant effects by attenuating inflammatory responses. However, the beneficial effect of Saururus chinensis leaves on arthritis has not been elucidated. Thus, we evaluated the water extract of Saururus chinensis leaves (SHW) using type II collagen-induced arthritis (CIA) mice models. METHODS: Quantitative analysis of major components from SHW was performed by HPLC. Arthritis was induced by injection of type II collagen. Each group was orally administered SHW (100 mg/kg and 500 mg/kg). Methotrexate (MTX) was used as a positive control. Serum levels of interleukin-6, TNF-alpha, and type II collagen IgG in the animal models were measured using ELISA. Histological features were observed by H&E staining. RESULTS: Quantitative analysis of SHW showed the contents as 56.4 ± 0.52 mg/g of miquelianin, 7.75 ± 0.08 mg/g of quercetin 3-O-(2"-O-ß -glucopyranosyl)-α-rhamnopyranoside, and 3.17 ± 0.02 mg/g of quercitrin. Treatment with 500 mg/kg SHW decreased the serum level of Interleukin-6 (IL-6), TNF-alpha, and collagen IgG in the CIA model. Moreover, SHW treatment diminished the swelling of hind limbs and monocyte infiltration in blood vessels in CIA animal models. The results indicate that SHW could decrease CIA-induced arthritis in vivo. CONCLUSIONS: The results indicate that SHW could be used to improving arthritis by reducing inflammatory factors (IL-6 and TNF-alpha). However, further experiments are required to determine how SHW influences signal transduction in animal models.

Matrix Solid-Phase Dispersion Combined with HPLC-DAD for Simultaneous Determination of Nine Lignans in Saururus chinensis.

A simple and rapid method, based on matrix solid-phase dispersion (MSPD) and high-performance liquid chromatography (HPLC) was developed for simultaneous determination of nine lignans, including (-)-(7R,8R)-machilin D (Wang, C., Wang, P., Chen, X., Wang, W., Jin, Y.; Saururus chinensis (Lour.) Baill blocks enterovirus 71 infection by hijacking MEK1-ERK signaling pathway; Antiviral Research, (2015); 119:47-56), dihydroguaiaretic acid (Quan, Z., Lee, Y.J., Yang, J.H., Lu,Y., Li,Y., Lee,Y.K., et al.; Ethanol extracts of Saururus chinensis suppress ovalbumin-sensitization airway inflammation; Journal of Ethnopharmacology, (2010); 132:143-149.), sauchinone (Zhuang, T., Liang, J.Y., Sun, J.B., Wu, Y., Huang, L.R., Qu, W.; Secondary metabolites from Saururus chinensis and their chemotaxonomic significance; Biochemical Systematics and Ecology, (2014); 56:95-98.), rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan (Tsai, W.J., Shen, C.C., Tsai, T.H., Lin, L.C.; Lignans from the aerial parts of Saururus chinensis: isolation, structural characterization, and their effects on platelet aggregation; Journal of Natural Products, (2014); 77:125-131), licarin A (Cui, H., Xu, B., Wu, T., Xu, J., Yuan, Y., Gu, Q.; Potential antiviral lignans from the roots of Saururus chinensis with activity against Epstein-Barr virus lytic replication; Journal of Natural Products, (2014); 77:100-110.), manassantin A (Lu, Y., Piao, D., Zhang, H., Li, X., Chao, G.H., Park, S.J., et al.; Saucerneol F inhibits tumor necrosis factor-alpha and IL-6 production by suppressing Fyn-mediated pathways in FcepsilonRI-mediated mast cells; Food and Chemical Toxicology, (2013); 59:696-702.), saurucinol I (Kwon, O.E., Lee, H.S., Lee, S.W., Chung, M.Y., Bae, K.H., Rho, M.C., et al.; Manassantin A and B isolated from Saururus chinensis inhibit TNF-α-induced cell adhesion molecule expression of human umbilical vein endothelial cells; Archives of Pharmacal Research, (2005); 28:55-60.), manassantin B (Hwang, B.Y., Lee, J.H., Jung, H.S., Kim, K.S., Nam, J.B., Hong, Y.S., et al.; Sauchinone, a lignan from Saururus chinensis, suppresses iNOS expression through the inhibition of transactivation activity of RelA of NF-κB; Planta Medica, (2003); 69:1096-01.) and licarin B (Hwang, B.Y., Lee, J.H., Nam, J.B., Hong, Y.S., Lee, J.J.; Lignans from Saururus chinensis inhibiting the transcription factor NF-κB; Phytochemistry, (2003); 64:765-771.) in Saururus chinensis. The parameters of MSPD were optimized to be that 0.2 g of sample, blended with 0.4 g silica gel, and eluted with 5 mL of methanol. The separation was carried out on a C18 column with acidified aqueous acetonitrile gradients. The established method was fully validated in terms of linearity (r2 ≥ 0.9994), sensitivity, precision (RSD ≤ 3.18%), repeatability (RSD ≤ 3.02%) as well as recovery (93.49-103.52%), and subsequently applied to six samples of S. chinensis from different areas. The MSPD extraction promoted higher extraction yields of nine lignans, lower solvent sample and solvent consumption.

Enzyme Kinetics and Molecular Docking Studies on Cytochrome 2B6, 2C19, 2E1, and 3A4 Activities by Sauchinone.

Sauchinone, an active lignan isolated from the aerial parts of Saururus chinensis (Saururaceae), exhibits anti-inflammatory, anti-obesity, anti-hyperglycemic, and anti-hepatic steatosis effects. As herb-drug interaction (HDI) through cytochrome P450s (CYPs)-mediated metabolism limits clinical application of herbs and drugs in combination, this study sought to explore the enzyme kinetics of sauchinone towards CYP inhibition in in vitro human liver microsomes (HLMs) and in vivo mice studies and computational molecular docking analysis. In in vitro HLMs, sauchinone reversibly inhibited CYP2B6, 2C19, 2E1, and 3A4 activities in non-competitive modes, showing inhibition constant (Ki) values of 14.3, 16.8, 41.7, and 6.84 µM, respectively. Also, sauchinone time-dependently inhibited CYP2B6, 2E1 and 3A4 activities in vitro HLMs. Molecular docking study showed that sauchinone could be bound to a few key amino acid residues in the active site of CYP2B6, 2C19, 2E1, and 3A4. When sibutramine, clopidogrel, or chlorzoxazone was co-administered with sauchinone to mice, the systemic exposure of each drug was increased compared to that without sauchinone, because sauchinone reduced the metabolic clearance of each drug. In conclusion, when sauchinone was co-treated with drugs metabolized via CYP2B6, 2C19, 2E1, or 3A4, sauchinone-drug interactions occurred because sauchinone inhibited the CYP-mediated metabolic activities.

ent-Sauchinone as Potential Anticancer Agent Inhibiting Migration and Invasion of Human Liver Cancer Cells via Suppressing the STAT3 Signaling Pathway.

ent-Sauchinone, a lignan isolated from Saururus chinensis (Lour.) Baill., was reported that it could modulate the expression of signal transducer and activator of transcription 3 (STAT3). Since STAT3 plays a key role in invasion, migration, and metastasis of cancer, we investigated whether ent-sauchinone could exert promising inhibitory effects on the invasion and migration of the metastatic human liver cancer cell line SMMC-7721 in the present study. ent-Sauchinone was extracted from dried herbs of Saururus chinensis (Lour.) Baill. Human liver cancer cell lines SMMC-7721 and HCCLM3 were used to test the effect of ent-sauchinone on cell viability. The IC50 values and time-dependent effect of ent-sauchinone were determined by MTT assay. Cell migration and invasion of SMMC-7721 were evaluated by the wound healing test and transwell assay respectively, the known anti-metastasis agent curcumin was used as a positive control. Western blotting assay was used to investigate relevant molecular mechanisms of cell invasion and migration. Though ent-sauchinone didn't show high cytotoxicity, the wound healing assay and transwell migration assay revealed a profound impairment in the metastatic potential of SMMC-7721 cells due to down-regulation of N-cadherin, MMP-2, and MMP-9 proteins induced by inhibiting the phosphorylation of STAT3. These findings suggest that ent-sauchinone could be used as a promising agent to treat cancer metastasis.

Simultaneous determination of four amides in Saururus chinensis by matrix solid phase dispersion and high-performance liquid chromatography method.

A rapid and simple analytical method was established for the determination of four amides (N-p-trans-coumaroyltyramine, aristolactam AⅡ, sauristolactam and aristolactam BⅡ) in Saururus chinensis by matrix solid phase dispersion (MSPD) and high-performance liquid chromatography-diode array detector (HPLC-DAD). In the optimized MSPD, 0.2 g S. chinensis powder was blended with 0.4 g silica gel, and 5 mL methanol was selected as elution solvent. The MSPD extraction achieved higher extraction recovery of four amides, and required less sample, solvent and preparation time, comparing with the conventional methods (Soxhlet and ultrasonic extraction). The assay was performed on a TSK gel ODS-100Z column (4.6 mm × 250 mm, 5 µm) at 30 °C. Acetonitrile and 0.4% acetic acid aqueous solution was used as mobile phase by gradient elution at the flow rate of 1.0 mL/min. The detection wavelength was 280 nm. All the analytes showed good linear regression (R2 ≥ 0.9998) within the concentration ranges. The validated method showed good precision and stability with relative standard deviations (RSDs) ≤ 3.18%. The recoveries were in the range of 96.57-99.65%, with RSDs less than 2.74%.

Two new lignans from Saururus chinensis.

Two new lignans, (Z)-14-bis(3',4'-dimethoxyphenyl)-2,3-dimethylbut-2-ene-1,4-dione (1), threo-2-methyl-3-oxo-1-(3',4',5'-trimethoxyphenyl)butyl-3″,4″-dimethoxybenzoate (2), together with 15 known derivatives (3-17) were isolated from Saururus chinensis. Their structures were determined on the basis of spectral data, including 1D and 2D NMR experiments and HREIMS spectra. The antitumour activity was screened by MTT assay, compounds 1, 2, 3, 5, 9-11 and 13-15 showed no cytotoxic activity against HL-60, SMMC-7721, A549, MCF-7 and SW480 cell lines.

Sauruchinenols A and B, unprecedented monocyclic diterpenes with new carbon skeleton from the aerial parts of Saururus chinensis.

Sauruchinenols A (1) and B (2), two novel monocyclic diterpenes with unique carbon skeleton, as well as two new structurally related diterpenes, sauruchinenols C (3) and D (4), were isolated from the aerial part of Saururus chinensis. Their structures were elucidated based on the analysis of spectroscopic data. A hypothetical biogenetic pathway for sauruchinenols A and B was proposed.