Undescribed sesquiterpenoids with NO production inhibitory activity from oleo-gum resin of Commiphora myrrha.

Six undescribed cadinane sesquiterpenoids (1-6), two undescribed guaiane sesquiterpenoids (7-8), and an undescribed germacrane sesquiterpenoid (9) were isolated from the oleo-gum resin of Commiphora myrrha. Their structures were determined by the analysis of 1D/2D NMR and HRESIMS data, as well as quantum chemical ECD and NMR calculations. All the sesquiterpenoids were evaluated for their NO production inhibitory activity in LPS-stimulated RAW 264.7 mouse monocyte-macrophages. The results revealed that commiphone A (1) and commipholide D (7) exhibited significant inhibitory effect on NO generation with IC50 values of 18.6 ± 2.0 and 37.5 ± 1.5 µM, respectively. Furthermore, 1 and 7 dose-dependently inhibited the mRNA expression of inflammatory cytokines IL-1ß, IL-6 and TNF-α induced by LPS in the RAW264.7 cells, indicating that 1 and 7 possess potent anti-inflammatory activity in vitro.

Cetuximab enhances oridonin-induced apoptosis through mitochondrial pathway and endoplasmic reticulum stress in laryngeal squamous cell carcinoma cells.

Cetuximab plus oridonin showed a synergistic way to kill laryngeal squamous cell carcinoma (LSCC), as been reported previously. The present work further mechanistically extended action of the synergistic effects of combination treatment. Firstly, two LSCC cells displayed higher sensitivity to oridonin, whereas both low EGFR expression tumor cells and EGFR knockdown LSCC cells were less sensitive to oridonin. Next, cetuximab/oridonin significantly enhanced the mitochondrial apoptosis through NF-κB. Meanwhile, PI3K/Akt and JAK2/STAT3 pathways are associated with the nucleus translocation of NF-κB by combination treatment. Additionally, cetuximab enhanced oridonin-promoted ER stress-related apoptosis. Interestingly, both ER stress and mitochondrial apoptosis by combination treatment are abrogated by ROS scavenger. Furthermore, oridonin/cetuximab induced ROS production after 1.5 h, followed by G2/M arrest and apoptosis, indicating that ROS generation might be an early and key event. Taken together, cetuximab enhances oridonin-induced ER stress and mitochondrial apoptotic pathway, which contributes to the synergistic antitumor effects of cetuximab/oridonin.

Metabolic profiles of corydaline in rats by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry.

1. Corydaline, an isoquinoline alkaloid obtained from the rhizomes of Corydalis yanhusuo, exhibits anti-acetylcholinesterase, anti-angiogenic, anti-allergic and gastric-emptying activities. In this study, a rapid and reliable ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) method was developed and employed for the comprehensive study of the metabolites of corydaline in rats. 2. Altogether, 43 metabolites were identified in the plasma (11), bile (9), urine (34) and feces (21) of rats after oral administration of corydaline at a dose of 4.5mg/kg. 3. It was demonstrated that demethylation, hydroxylation, sulfation and glucuronidation were the major metabolic transformation pathways. Among these, two metabolites were identified as tetrahydropalmatine and isocorybulbine, and 33 phase I and phase II products were inferred to be new metabolites arising from the in vivo metabolism of corydaline. 4. Importantly, this research provides scientific and reliable support for full understanding of the metabolic profiles of corydaline and the results could help to elucidate its safety and efficacy.

Two pairs of phenolic enantiomers from the leaves of Eucommia ulmoides Oliver.

Two pairs of new phenolic enantiomers, (+)-eucophenolic A (1a), (-)-eucophenolic B (1b), (-)-eucophenolic C (2a), (+)-eucophenolic D (2b) were isolated from the leaves of Eucommia ulmodies Oliver by chiral enantiomeric resolution. Their structures were elucidated based on extensive spectroscopic analysis. The absolute configurations of 1a/1b and 2a/2b were determined by empirical method and the calculated ECD and OR. All compounds were tested for Hep G2 tumour cell lines. However, no compounds showed potential cytotoxic activities against Hep G2 in vitro.

Molecular mechanisms of apoptosis and autophagy elicited by combined treatment with oridonin and cetuximab in laryngeal squamous cell carcinoma.

Combined oridonin (ORI), a natural and safe kaurene diterpenoid isolated from Rabdosia rubescens, and cetuximab (Cet), an anti-EGFR monoclonal antibody, have been reported to exert synergistic anti-tumor effects against laryngeal squamous cell carcinoma (LSCC) both in vitro and in vivo by our group. In the present study, we further found that ORI/Cet treatment not only resulted in apoptosis but also induced autophagy. AMPK/mTOR signaling pathway was found to be involved in the activation of autophagy in ORI/Cet-treated LSCC cells, which is independent of p53 status. Additionally, chromatin immunoprecipitation (ChIP) assay showed that ORI/Cet significantly increased the binding NF-κB family member p65 with the promotor of BECN 1, and p65-mediated up-regulation of BECN 1 caused by ORI/Cet is coupled to increased autophagy. On the other hand, we demonstrated that either Beclin 1 SiRNA or autophagy inhibitors could increase ORI/Cet induced-apoptosis, indicating that autophagy induced by combination of the two agents plays a cytoprotective role. Interestingly, 48 h after the combined treatment, autophagy began to decrease but apoptosis was significantly elevated. Our findings suggest that autophagy might be strongly associated with the antitumor efficacy of ORI/Cet, which may be beneficial to the clinical application of ORI/Cet in LSCC treatment.

Two pairs of phenylpropanoid enantiomers from the leaves of Eucommia ulmoides.

Two pairs of phenylpropanoid enantiomers, (+)-(7S,8S)-alatusol D (1a), (-)-(7R,8R)-alatusol D (1b), (-)-(7S,8R)-alatusol D (2a) and (+)-(7R,8S)-alatusol D (2b) were isolated from the leaves of Eucommia ulmoides Oliver. Among them, 1a and 2b were firstly obtained by chiral enantiomeric resolution. Their structures were elucidated based on extensive spectroscopic analysis and the induced CD (ICD) spectrum caused by adding Mo2(AcO)4 in DMSO. All compounds were tested on Hep G2 tumor cell lines. However, none of the compounds showed potential cytotoxic activity against Hep G2 in vitro.

Two sulfonate metabolites of physalin A in rats.

1. Physalin A is a bioactive withanolide isolated from the natural plant Physalis alkekengi var. franchetii (Solanaceae), a common traditional Chinese herbal medicine. This study aims to investigate the metabolites of physalin A in vivo. 2. Two metabolites (M1 and M2) were characterized as sulfonate metabolites in the feces obtained from rats treated with physalin A orally at a dose of 15 mg/kg/day for 3 days, by application of a UPLC-Q/TOF-MS method. Furthermore, formation of the two sulfonate metabolites was verified by chemical synthesis and NMR, including 1H NMR, 13C NMR and two-dimensional NMR. The structures of M1 and M2 were identified to be 3α-sulfo-2,25ß,27-trihydrophysalin A and 3α,27-disulfo-2,25α-dihydrophysalin A, respectively. 3. In summary, this study indicated that physalin A could be biotransformed to sulfonate metabolites with strong polarity, which contributed to the elimination of physalin A. A rare metabolic pathway has been revealed in this study.

Nine pairs of megastigmane enantiomers from the leaves of Eucommia ulmoides Oliver.

Nine pairs of megastigmane enantiomers (1a/1b-9a/9b), comprising two new compounds (6S,9R)-blumenol C (7b), (6S,9S)-blumenol C (8b), two pairs of enantiomers (+)-(6R)-eucomegastigmane A (1a), (-)-(6S)-eucomegastigmane A (1b), (+)-(3S,4S)-eucomegastigmane B (5a), (-)-(3R,4R)-eucomegastigmane B (5b) isolated by chiral resolution firstly, and twelve known compounds, were isolated from the leaves of Eucommia ulmoides Oliver. Their structures were elucidated based on extensive spectroscopic analysis. Absolute configurations of the megastigmane enantiomers were assigned by comparing experimental ECD and OR with calculated ECD and OR. Docking-based virtual screening of all compounds showed that megastigmane enantiomers have weak intermolecular interactions with the binding site residues of angiotensin-converting enzyme (ACE) and angiotensin II type 1 receptor (AT1R).

Megastigmane glycosides from leaves of Eucommia ulmoides Oliver with ACE inhibitory activity.

Four new megastigmane glycosides, eucomegastigsides A-D (2, 3, 5 and 7), together with three known megastigmane glycosides, (6R, 7E, 9R)-9-hydroxy-4, 7-megastigmadien-3-one-9-O-[α-l-arabinopyranosyl-(l→6)-ß-d-glucopyranoside (1), foliasalacioside B1 (4) and eleganoside A (6), were isolated from the leaves of Eucommia ulmoides Oliver. Their anti-hypertensive effect was investigated in vitro based on the inhibition of Angiotensin Converting Enzyme (ACE) using HPLC. The results showed that the isolates (2, 3, 4, 5, 7) had moderate inhibitory effects on ACE in vitro compared with captopril.

Locally and traditionally used Ligusticum species - A review of their phytochemistry, pharmacology and pharmacokinetics.

ETHNOPHARMACOLOGICAL RELEVANCE: Ligusticum species (Umbelliferae) have been widely used in traditional Chinese medicine, Korean folk medicine and Native American medicine for their medicinal and nutritional value. Decoctions of the rhizomes are used in treatment and prophylaxis of migraine, anemia and cardiovascular conditions including stroke. AIM OF STUDY: This review is intended to fully compile the constituents of locally and traditionally used Ligusticum species, present their bioactivities and highlight potential leads for future drug design, and thus, provide a reference for further research and application of these species. Emphasis is also placed on current trends in the pharmacokinetic studies of the major constituents. METHODS: The literature discussed is derived from readily accessible papers spanning the early 1990s to the end of 2015. Information was collected from journals, books and online searches (Google Scholar, PubMed, ScienceDirect, SciFinder, Springerlink and CNKI). RESULTS: The major phytoconstituents, 154 of which are presented in this review, include alkaloids, phthalides and phenolic acids. The crude extracts and isolated constituents have exhibited a wide range of in vitro and in vivo pharmacologic effects, including cardioprotective, antioxidant, anti-inflammatory and neuroprotective activities. The bioactive alkaloid tetramethylpyrazine (TMP) has attracted the most attention for its potent effect on calcium channels, anti-platelet as well as anti-inflammatory effects. Pharmacokinetic studies of major constituents have also been summarized. CONCLUSION: The pthalides, organic acids and alkaloids of Ligusticum species have emerged as a good source of traditional medicines for the management of cardio- and cerebrovascular conditions, inflammation and neurogenerative disorders. The species discussed in this review have demonstrated wide pharmacological actions and have great potential to yield multipotent drugs if challenges such as poor bioavailability, solubility and toxicological profiles are addressed. Apart from the rhizomes, pharmacological activities of other botanical parts also need to be studied further. Expansion of research to cover other species in the Ligusticum genus would provide more opportunities for the discovery of new bioactive principles.

Combined oridonin with cetuximab treatment shows synergistic anticancer effects on laryngeal squamous cell carcinoma: involvement of inhibition of EGFR and activation of reactive oxygen species-mediated JNK pathway.

Epidermal growth factor receptor (EGFR), a transmembrane glycoprotein, is expressed at high levels in a large proportion of laryngeal squamous cell carcinoma (LSCC). Cetuximab (Cet), an anti-EGFR monoclonal antibody, has limited clinical outcome for patients with head and neck squamous cell carcinoma. Our previous studies showed that oridonin (ORI), a natural and safe kaurene diterpenoid isolated from Rabdosia rubescens, inhibited cell growth in HEp-2 cells through inhibition of EGFR phosphorylation. The aim of the present study was to determine whether ORI could improve the anticancer efficacy of Cet on LSCC. We observed that the combination with Cet and ORI synergistically inhibited cell growth associated with Fas-mediated apoptosis and G2/M phase arrest in two LSCC cell lines (HEp-2 and Tu212 cells). Moreover, combination treatment caused cell death associated with suppression of p-EGFR and activation of reactive oxygen species (ROS)-mediated JNK pathway. In nude mice bearing HEp-2 xenografts, ORI plus Cet caused a significant tumor regression through induction of apoptosis and inhibition of proliferation with no side-effect. Together, our findings suggest that the combination of ORI and Cet has the potential to enhance tumor responses and may significantly improve therapeutic outcomes in LSCC.

Downregulation of CREB Promotes Cell Proliferation by Mediating G1/S Phase Transition in Hodgkin Lymphoma.

The cyclic-AMP response element-binding protein (CREB), a well-known nuclear transcription factor, has been shown to play an essential role in many cellular processes, including differentiation, cell survival, and cell proliferation, by regulating the expression of downstream genes. Recently, increased expression of CREB was frequently found in various tumors, indicating that CREB is implicated in the process of tumorigenesis. However, the effects of CREB on Hodgkin lymphoma (HL) remain unknown. To clarify the role of CREB in HL, we performed knockdown experiments in HL. We found that downregulation of CREB by short hairpin RNA (shRNA) resulted in enhancement of cell proliferation and promotion of G1/S phase transition, and these effects can be rescued by expression of shRNA-resistant CREB. Meanwhile, the expression level of cell cycle-related proteins, such as cyclin D1, cyclin E1, cyclin-dependent kinase 2 (CDK2), and CDK4, was elevated in response to depletion of CREB. Furthermore, we performed chromatin immunoprecipitation (ChIP) assay and confirmed that CREB directly bound to the promoter regions of these genes, which consequently contributed to the regulation of cell cycle. Consistent with our results, a clinical database showed that high expression of CREB correlates with favorable prognosis in B-cell lymphoma patients, which is totally different from the function of CREB in other cancers such as colorectal cancer, acute myeloid leukemia, and some endocrine cancers. Taken together, all of these features of CREB in HL strongly support its role as a tumor suppressor gene that can decelerate cell proliferation by inhibiting the expression of several cell cycle-related genes. Our results provide new evidence for prognosis prediction of HL and a promising therapeutic strategy for HL patients.

A validated LC-MS/MS method for determination of periplogenin in rat plasma and its application in pharmacokinetic study.

A method coupling high performance liquid chromatography with tandem mass spectrometry has been developed and validated for quantifying periplogenin in rat plasma using psoralen as an internal standard (IS). Plasma samples were pretreated using a simple liquid-liquid extraction with ethyl acetate and the chromatographic separation of periplogenin and psoralen was achieved on a Waters XBridge™ BEH C18 column with 0.1% formic acid and acetonitrile as mobile phase at a flow rate of 0.4mL/min. The detection was performed on a positive ion mode with electrospray ionization (ESI) source. The optimized ion transition pairs for quantitation were m/z 391.3→m/z 337.2 for periplogenin and m/z 187.0→m/z 131.0 for IS. The total run time was 9.0min. The calibration curve was linear over the range of 0.2-250ng/mL (r>0.99) with the lower limit of quantitation (LLOQ) at 0.2ng/mL. The intra- and inter-day precision were below 9.85% and the mean accuracy were from -10.03% to 10.26%. The average recoveries of periplogenin in plasma ranged from 85.1% to 95.6%. The proposed method was successfully applied in evaluating the pharmacokinetics of periplogenin after an oral dose of 30mg/kg Cortex Periplocae extract in rats.

Cuscuta chinensis Lam.: A systematic review on ethnopharmacology, phytochemistry and pharmacology of an important traditional herbal medicine.

ETHNOPHARMACOLOGICAL RELEVANCE: Cuscuta chinensis Lam. has found its use as a traditional medicine in China, Korea, Pakistan, Vietnam, India and Thailand. It is commonly used as an anti-aging agent, anti-inflammatory agent, pain reliever and aphrodisiac. To provide an overview of the ethnopharmacology, phytochemistry, pharmacokinetics, pharmacology and clinical applications of Cuscuta chinensis, as well as being an evidence base for further research works of the plant. MATERIALS AND METHODS: The present review covers the literature available from 1985 to 2014. The information was collected from journals, books, theses and electronic search (Google Scholar, PubMed, ScienceDirect, ESBCO, Springerlink and CNKI). Literature abstracts and full-text articles were analyzed and included in the review. RESULTS: Many phytochemicals have been isolated, identified and published to date, including: at least 18 flavonoids; 13 phenolic acids; 2 steroids; 1 hydroquinone; 10 volatile oils; 22 lignans; 9 polysaccharides; 2 resin glycosides; 16 fatty acids. These phytochemicals and plant extracts exhibit a range of pharmacological activities that include hepatoprotective, renoprotective, antiosteoporotic, antioxidant, anti-aging, antimutagenic, antidepressant, improve sexual function, abortifacient effects, etc. CONCLUSION: This present review offers primary information for further studies of Cuscuta chinensis. The in vitro studies and in vivo models have provided a bioscientific explanation for its various ethnopharmacological uses and pharmacological activities (most notably antioxidant effects) especially in the prevention of hepatic disease and renal failure. It is necessary and important to do more pharmacokinetic and toxicological research works on human subjects in order to inform the possible active compounds in the body and validate its safety in clinical uses.