Antiproliferation and apoptosis induction of paeonol in HepG2 cells

Metformin Suppresses Stemness of Non-Small-Cell Lung Cancer Induced by Paclitaxel through FOXO3a

Cancer stem cells (CSCs) play a pivotal role in drug resistance and metastasis. Among the key players, Forkhead box O3a (FOXO3a) acts as a tumor suppressor. This study aimed to unravel the role of FOXO3a in mediating the inhibitory effect of metformin on cancer stemness derived from paclitaxel (PTX)-resistant non-small-cell lung cancer (NSCLC) cells. We showed that CSC-like features were acquired by the chronic induction of resistance to PTX, concurrently with inactivation of FOXO3a. In line with this, knockdown of FOXO3a in PTX-sensitive cells led to changes toward stemness, while overexpression of FOXO3a in PTX-resistant cells mitigated stemness in vitro and remarkably curbed the tumorigenesis of NSCLC/PTX cells in vivo. Furthermore, metformin suppressed the self-renewal ability of PTX-resistant cells, reduced the expression of stemness-related markers (c-MYC, Oct4, Nanog and Notch), and upregulated FOXO3a, events concomitant with the activation of AMP-activated protein kinase (AMPK). All these changes were recapitulated by silencing FOXO3a in PTX-sensitive cells. Intriguingly, the introduction of the AMPK dominant negative mutant offset the inhibitory effect of metformin on the stemness of PTX-resistant cells. In addition, FOXO3a levels were elevated by the treatment of PTX-resistant cells with MK2206 (an Akt inhibitor) and U0126 (a MEK inhibitor). Collectively, our findings indicate that metformin exerts its effect on FOXO3a through the activation of AMPK and the inhibition of protein kinase B (Akt) and MAPK/extracellular signal-regulated kinase (MEK), culminating in the suppression of stemness in paclitaxel-resistant NSCLC cells.

Paeonol repurposing for cancer therapy: From mechanism to clinical translation

Paeonol (PAE) is a natural phenolic monomer isolated from the root bark of Paeonia suffruticosa that has been widely used in the clinical treatment of some inflammatory-related diseases and cardiovascular diseases. Much preclinical evidence has demonstrated that PAE not only exhibits a broad spectrum of anticancer effects by inhibiting cell proliferation, invasion and migration and inducing cell apoptosis and cycle arrest through multiple molecular pathways, but also shows excellent performance in improving cancer drug sensitivity, reversing chemoresistance and reducing the toxic side effects of anticancer drugs. However, studies indicate that PAE has the characteristics of poor stability, low bioavailability and short half-life, which makes the effective dose of PAE in many cancers usually high and greatly limits its clinical translation. Fortunately, nanomaterials and derivatives are being developed to ameliorate PAE's shortcomings. This review aims to systematically cover the anticancer advances of PAE in pharmacology, pharmacokinetics, nano delivery systems and derivatives, to provide researchers with the latest and comprehensive information, and to point out the limitations of current studies and areas that need to be strengthened in future studies. We believe this work will be beneficial for further exploration and repurposing of this natural compound as a new clinical anticancer drug.

Paeonia × suffruticosa (Moutan Peony)-A Review of the Chemical Composition, Traditional and Professional Use in Medicine, Position in Cosmetics Industries, and Biotechnological Studies

The aim of this review is to perform a systematic review of scientific papers and an in-depth analysis of the latest research related to Paeonia × suffruticosa Andrews as a valuable plant species, important in pharmacy and cosmetology. P. × suffruticosa bark root-Moutan cortex is a medicinal raw material formerly known from traditional Chinese medicine (TCM) but less common in official European medicine. It was introduced for the first time in the European Pharmacopoeia Supplement 9.4 in 2018. In this work, the numerous possible applications of this raw material were depicted based on modern professional pharmacological studies documenting its very valuable medicinal values, including antioxidant, cytoprotective, anti-cancer, anti-inflammatory, cardioprotective, anti-atherosclerotic, anti-diabetic and hepatoprotective activities. The scientific studies indicated that the profile of raw material activity is mainly due to paeonol, paeoniflorin and 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose. Moreover, the significance of this plant (its different organs) in the production of cosmetics was underlined. P. × suffruticosa finds increasing application in cosmetology due to research on its chronic dermatitis, anti-aging and brightening effects. Furthermore, some biotechnological research has been described aimed at developing effective in vitro micropropagation protocols for P. × suffruticosa.

Quantitation of γ-Glutamylcysteine-Formaldehyde Conjugate in Formaldehyde- and Oxidative Stress-Exposed Cells by Liquid Chromatography-Tandem Mass Spectrometry

Humans are constantly exposed to formaldehyde (FA) of both exogenous and endogenous sources, and FA exposure is associated with the development of many human diseases, including cancers. Marker molecules that can provide information on exposure history and amounts will assist disease risk assessment and early interventions. To develop marker signatures of FA exposure, we explored in this study the conjugation reaction of FA with γ-glutamylcysteine (GGC), one of the precursors to glutathione biosynthesis, under physiologically relevant conditions. The results showed that the reaction produced a stable metabolite of FA, (S)-1-((((R)-2-amino-2-carboxyethyl)thio)methyl)-5-oxopyrrolidine-2-carboxylic acid (COCA). Using liquid chromatography-tandem mass spectrometry coupled to a stable isotope-dilution method, we then quantitated for the first time the formation of this novel metabolite in FA- and Fe²⁺-EDTA-exposed human cells. The results revealed the exposure time- and concentration-dependent formation of COCA in FA- or Fe²⁺-EDTA-exposed cells, suggesting that COCA may serve as a biomarker of FA and oxidative stress exposure. Furthermore, the study sheds light on a previously unknown protective role of GGC against FA and oxidative stress.

A novel organic cation transporter involved in paeonol transport across the inner blood-retinal barrier and changes in uptake in high glucose conditions

Paeonol exerts various pharmacological effects owing to its antiangiogenic, antioxidant, and antidiabetic activities. We aimed to investigate the transport mechanism of paeonol across the inner blood-retinal barrier both in vitro and in vivo. The carotid artery single injection method was used to investigate the retina uptake index of paeonol. The retina uptake index (RUI) value of [³H]paeonol was dependent on both concentration and pH. This value decreased significantly in the presence of imperatorin, tramadol, and pyrilamine when compared to the control. However, para-aminohippuric acid, choline, and taurine had no effect on the RUI value. Conditionally immortalized rat retina capillary endothelial cells (TR-iBRB cell lines) were used as an in vitro model of the inner blood-retinal barrier (iBRB). The uptake of [³H]paeonol by the TR-iBRB cell lines was found to be time-, concentration-, and pH-dependent. However, the uptake was unaffected by the absence of sodium or by membrane potential disruption. Moreover, in vitro structural analog studies revealed that [³H]paeonol uptake was inhibited in the presence of organic cationic compounds including imperatorin, clonidine and tramadol. This is consistent with the results obtained in vivo. In addition, transfections with OCTN1, 2 or plasma membrane monoamine transporter (PMAT) small interfering RNA did not affect paeonol uptake in TR-iBRB cell lines. Upon pre-incubation of these cell lines with high glucose (HG) media, [³H]paeonol uptake decreased and mRNA expression levels of angiogenetic factors, such as hypoxia inducible factor-1 (HIF-1) and vascular endothelial growth factor (VEGF) increased. However, after the pretreatment of unlabeled paeonol in HG conditions, the mRNA levels of VEGF and HIF-1 were comparatively reduced, and the [³H]paeonol uptake rate was restored. After being exposed to inflammatory conditions induced by glutamate, TNF-α, and LPS, paeonol and propranolol pretreatment significantly increased the uptake of both [³H]paeonol and [³H]propranolol in TR-iBRB cell lines compared to their respective controls. Our results demonstrate that the transport of paeonol to the retina across the iBRB may involve the proton-coupled organic cation antiporter system, and the uptake of paeonol is changed by HG conditions.

In vitro protective effects of Paeonia mascula subsp. hellenica callus extract on human keratinocytes

Natural ingredients have been used to improve the state of health in humans. The genus Paeonia has been studied only limited yet it’s reported to have many activities such as antioxidant and anti-inflammatory. To this context, here we focused on an endemic Paeonia species in Attica. This study aims to present the development of the Paeonia mascula subsp. hellenica callus extract and its pleiotropic bioactivity on human primary keratinocytes exploring its potential application as an active agent in skin-related products. This extract showed a high scavenging activity with high phenolic content and an interesting metabolic profile. At a molecular level, the study on the transcript accumulation of genes revealed that this extract exhibits in vitro skin-related protection properties by mediating mitochondrial energy, cell proliferation, immune and inflammatory response and positively regulates genes involved in epidermal and in stratum corneum function. Besides, the extract is proven not skin irritant on reconstructed human skin model. These findings indicate that the specific P. mascula subsp. hellenica extract possesses significant in vitro protection activity on human epidermis and provides new insights into its beneficial role in skin confirming that the advent of biotechnology contribution the past few decades.

Cancer-derived IgG involved in cisplatin resistance through PTP-BAS/Src/PDK1/AKT signaling pathway

OBJECTIVES

This study aimed to explore whether knockdown of cancer-derived IgG (CIgG) could enhance cisplatin-induced anti-cancer effects.

MATERIALS AND METHODS

Cancer-derived IgG was knocked down by siRNA or Tet-on shRNA in the absence or presence of cisplatin in WSU-HN6 or CAL27 cells. Cell proliferation, apoptosis, and mobility were evaluated using CCK-8, flow cytometry, and transwell assays, respectively. Molecular events were investigated using real-time PCR and Western blot assays.

RESULTS

Knockdown of CIgG significantly promoted cisplatin-induced apoptosis and inhibition of cell proliferation, migration, and invasion. Cisplatin upregulated CIgG expression and phosphorylation of AKT and PDK1, while knockdown of CIgG downregulated phosphorylation of AKT and PDK1, and blocked cisplatin-induced upregulation of AKT and PDK1 phosphorylation. Moreover, knockdown of CIgG blocked cisplatin-induced upregulation of Src phosphorylation, and knockdown of Src blocked cisplatin-induced upregulation of AKT and PDK1 phosphorylation. Overexpression of Src upregulated AKT and PDK1 phosphorylation. Furthermore, knockdown of CIgG upregulated PTP-BAS mRNA and protein expression, whereas cisplatin downregulated PTP-BAS protein, but not mRNA expression; knockdown of PTP-BAS upregulated phosphorylation of Src, PDK1, AKT, and blocked CIgG knockdown-mediated enhancement of cisplatin-induced inhibition of cell proliferation.

CONCLUSION

Knockdown of CIgG enhanced the anti-cancer effects of cisplatin through PTP-BAS/Src/PDK1/AKT signaling pathway in oral squamous cell carcinoma.

Characterization of phytochemicals in the roots of wild herbaceous peonies from China and screening for medicinal resources

Paeonia Radix Rubra (PRR) is a very common traditional Chinese medicine (TCM). The roots of Paeonia lactiflora and Paeonia anomala subsp. veitchii are used for the production of PRR. However, other species of section Paeonia in China are also used to produce PRR. The roots of section Paeonia from 20 populations of seven species and two subspecies in China were analyzed by high performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF- MS). A total of 21 metabolites were identified, including nine monoterpene glycosides, seven tannins, three phenols, one paeonol and one flavonoid. There were significant differences in the composition and content of metabolites among different populations. The relative contents of monoterpene glycosides and tannins were generally higher in most samples. Cluster analysis showed that 20 populations could be divided into four groups. Among them, the populations of P. lactiflora and Paeonia mairei were clustered together in one group. The content of paeoniflorin in P. lactiflora was high (>22.20 mg g^-1, dry weight, the same below), and the content of lactiflorin in P. mairei (>17.50 mg g^-1) was significantly higher than in other species (<2.30 mg g^-1). The monoterpene glycoside content in P. mairei (>51.60 mg g^-1) was significantly higher than in other species (<43.40 mg g^-1), suggesting that it could be useful medicinal germplasm for the development of monoterpene glycosides. In addition, some populations of Paeonia emodi, Paeonia sterniana and P. mairei may also be used as potential germplasm resources for use in PRR. Genetic and environmental factors resulted in differences in the composition and content of metabolites in different populations of the same species. Therefore, it is necessary to carefully consider the origin of Paeonia germplasm when selecting medicinal materials to be used as resources for the production of PRR.

High-dose ascorbic acid synergizes with anti-PD1 in a lymphoma mouse model

Major efforts are underway to identify agents that can potentiate effects of immune checkpoint inhibition. Here, we show that ascorbic acid (AA) treatment caused genomewide demethylation and enhanced expression of endogenous retroviral elements in lymphoma cells. AA also increased 5-hydroxymethylcytosine (5hmC) levels of CD8+ T cells and enhanced their cytotoxic activity in a lymphoma coculture system. High-dose AA treatment synergized with anti-PD1 therapy in a syngeneic lymphoma mouse model, resulting in marked inhibition of tumor growth compared with either agent alone. Analysis of the intratumoral epigenome revealed increased 5hmC with AA treatment, consistent with in vitro findings. Analysis of the tumor immune microenvironment revealed that AA strikingly increased intratumoral infiltration of CD8+ T cells and macrophages, suggesting enhanced tumor immune recognition. The combination treatment markedly enhanced intratumoral infiltration of macrophages and CD8+ T lymphocytes, granzyme B production by cytotoxic cells (cytotoxic T cells and natural killer cells), and interleukin 12 production by antigen-presenting cells compared with single-agent anti-PD1. These data indicate that AA potentiates anti-PD1 checkpoint inhibition through synergistic mechanisms. The study provides compelling rationale for testing combinations of high-dose AA and anti-PD1 agents in patients with aggressive B cell lymphoma as well as in preclinical models of other malignancies.

Isolation of Strong Antioxidants from Paeonia Officinalis Roots and Leaves and Evaluation of Their Bioactivities

Paeonia officinalis extracts from leaves and roots were tested for their antioxidant potential using in vitro chemical (Folin-Ciocalteu, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), oxygen radical absorbance capacity (ORAC), hydroxyl radical antioxidant capacity (HORAC), hydroxyl radical scavenging capacity HOSC)) and cellular antioxidant activity (CAA) assays. Leaf extracts were stronger antioxidants than root extracts, while methanol was a more effective solvent than water in chemical assays. However, the selected water extract of leaves was a stronger antioxidant in CAA than the methanol extract (0.106 vs. 0.046 µmol quercetin equivalents/mg). Twenty compounds were identified by ultra performance liquid chromatography-quadrupole-time-of-flight (UPLC-Q-TOF) mass spectrometer, while on-line screening of their antioxidant capacity by high performance liquid chromatography (HPLC) with a DPPH^•-scavenging detector revealed that gallic acid derivatives are the major peony antioxidants. Root water and leaf methanol extracts inhibited α-amylase in a dose dependent manner. The IC₅₀ value for the strongest inhibitor, the methanol extract of leaves, was 1.67 mg/mL. In addition, the cytotoxicity assessment of extracts using human Caco-2 cells demonstrated that none of them possessed cytotoxic effects.

Involvement of a Novel Organic Cation Transporter in Paeonol Transport Across the Blood-Brain Barrier

Paeonol has neuroprotective function, which could be useful for improving central nervous system disorder. The purpose of this study was to characterize the functional mechanism involved in brain transport of paeonol through blood-brain barrier (BBB). Brain transport of paeonol was characterized by internal carotid artery perfusion (ICAP), carotid artery single injection technique (brain uptake index, BUI) and intravenous (IV) injection technique in vivo. The transport mechanism of paeonol was examined using conditionally immortalized rat brain capillary endothelial cell line (TR-BBB) as an in vitro model of BBB. Brain volume of distribution (V_D) of [³H]paeonol in rat brain was about 6-fold higher than that of [¹⁴C]sucrose, the vascular space marker of BBB. The uptake of [3H]paeonol was concentration-dependent. Brain volume of distribution of paeonol and BUI as in vivo and inhibition of analog as in vitro studies presented significant reduction effect in the presence of unlabeled lipophilic compounds such as paeonol, imperatorin, diphenhydramine, pyrilamine, tramadol and ALC during the uptake of [³H]paeonol. In addition, the uptake significantly decreased and increased at the acidic and alkaline pH in both extracellular and intracellular study, respectively. In the presence of metabolic inhibitor, the uptake reduced significantly but not affected by sodium free or membrane potential disruption. Similarly, paeonol uptake was not affected on OCTN2 or rPMAT siRNA transfection BBB cells. Interestingly. Paeonol is actively transported from the blood to brain across the BBB by a carrier mediated transporter system.

A paeonol derivative, YPH-PA3 promotes the differentiation of monocyte/macrophage lineage precursor cells into osteoblasts and enhances their autophagy

Previous studies have indicated that paeonol inhibits RANKL-induced osteoclastogenesis by inhibiting the ERK, p38, and NF-κB pathway. We modified paeonol to form a new compound, YPH-PA3, and found that it promoted osteoclastogenesis rather than inhibited it the way paeonol does. The aim of this study is to investigate the mechanisms involved in YPH-PA3-promoted osteoclastogenesis. YPH-PA3-promoted differentiation of RAW264.7 cells (human monocytes) into osteoclasts is activated through ERK/p38/JNK phosphorylation, affecting c-FOS, NF-κB, and NFATc2. Real-time quantitative PCR and western blot revealed an increased expression of autophagy-related markers during YPH-PA3-induced osteoclastogenesis. We also demonstrated the relationship between p62/LC3 localization and F-actin ring formation by double-labeling immunofluorescence. Knockdown of p62 small-interfering RNA (siRNA) attenuated YPH-PA3-induced expression of autophagy-related genes. Our study results indicated that p62 may play a role in YPH-PA3-induced autophagy and osteoclastogenesis, which may help to develop a novel therapeutic strategy against osteoclastogenesis-related diseases.

Proteasome Inhibitor Carbobenzoxy-L-Leucyl-L-Leucyl-L-Leucinal (MG132) Enhances Therapeutic Effect of Paclitaxel on Breast Cancer by Inhibiting Nuclear Factor (NF)-κB Signaling

Background

Carbobenzoxy-L-leucyl-L-leucyl-L-leucinal (MG132), a peptide aldehyde proteasome inhibitor, can inhibit tumor progression by inactivating nuclear factor (NF)-κB signaling. Paclitaxel (PTX) is part of a routine regimen for the treatment of breast cancer. However, activation of the NF-κB pathway after treatment with PTX confers insensitivity to this drug. This study investigated the potential effect of MG132 as a co-treatment with PTX against breast cancer, and clarifies the underlying molecular mechanisms.

Material/Methods

Breast cancer cells were treated with PTX, MG132, or PTX plus MG132, and the therapeutic effects were evaluated phenotypically. A mouse model of breast cancer was used to determine the combined effect of PTX plus MG132 in vivo.

Results

Treatment with PTX plus MG132 suppressed aggressive phenotypes of breast cancer cells more effectively than PTX alone. Consistently, MG132 also enhanced the suppressive effect of PTX on tumor growth in C57BL/6 mice. Significantly, activation of the NF-κB pathway by PTX was attenuated by MG132.

Conclusions

Based on our findings, we suggest the application of MG132 in clinical practice in combination with PTX for the treatment of breast cancer.

Paeonol exerts potential activities to inhibit the growth, migration and invasion of human gastric cancer BGC823 cells via downregulating MMP‑2 and MMP‑9

Paeonol (Pae) is an herbal extract that has attracted extensive attention for its anti-cancer effects demonstrated by a number of studies, which have predominantly demonstrated inhibition of cell proliferation and induction of apoptosis. The influence of Pae on cancer cell metastasis has been less widely reported. The present study aimed to investigate the under-reported effects of Pae on the growth, invasion and migration of poorly differentiated BGC823 gastric cancer cells with strong invasive and metastatic abilities. The anti-proliferative and pro-apoptotic effects of Pae on BGC823 cells were verified by Cell Counting kit-8 and Annexin V-fluorescein isothiocyanate/propidium iodide assays. Cell scratch-wound healing and Transwell methods were applied, and it was demonstrated that Pae could exert inhibitory activities on the invasion and migration of BGC823 cells. Furthermore, it was indicated by western blot analysis that Pae could downregulate the protein expression levels of matrix metalloproteinase (MMP)-2 and −9 in a concentration-dependent manner, which may support a novel potential mechanism accounting for its anti-cancer effects on gastric cancer.

Paeonol enhances the sensitivity of human ovarian cancer cells to radiotherapy-induced apoptosis due to downregulation of the phosphatidylinositol-3-kinase/Akt/phosphatase and tensin homolog pathway and inhibition of vascular endothelial growth factor

Radiotherapy is a vital and effective method to treat solid tumors. However, in many tumor types, development of resistance of cancer cells and cytotoxicity in normal tissues presents a major therapeutic problem. It is therefore crucial to identify and develop novel sensitizing agents that may improve the response to radiation therapy without causing any adverse effects. The present study aimed to investigate whether paeonol, a bioactive flavonoid, was able to confer sensitivity to radiation in human ovarian cancer cells. The human ovarian cancer cell lines SKOV-3 and OVCAR-3 were exposed to varying doses of radiation (2, 4 or 6 Gy) in the presence or absence of paeonol (25, 50 or 100 µM). Radiosensitivity was assessed by measuring cell viability using a CCK-8 assay and Annexin V/PI staining. Expression of vascular endothelial growth factor (VEGF), hypoxia inducible factor-1α (HIF-1α), proteins of the phosphatidylinositol-3-kinase (PI3K)/Akt pathway and apoptotic pathway proteins [caspase-3, Bcl-2-associated death promoter, B-cell lymphoma (Bcl)-2, Bcl-2-associated X and Bcl-extra large (Bcl-xL)] were also assessed. Paeonol treatment enhanced apoptosis of SKOV-3 and OVCAR-3 cells that were exposed to radiation. The expression of Bcl-2 and Bcl-xL were markedly upregulated in these cells. Treatment with paeonol concentrations of 50 and 100 µM caused a significant downregulation of VEGF, HIF-1α and PI3K/Akt pathway proteins. Paeonol effectively enhanced the sensitivity of ovarian cancer cells to radiation by significantly altering regulation of the proteins of the PI3K/Akt pathway, in addition to downregulating VEGF and HIF-1α.

In vitro targeting of colon cancer cells using spiropyrazoline oxindoles

We report on the synthesis and biological evaluation of a library of twenty-three spiropyrazoline oxindoles. The antiproliferative activity of the chemical library was evaluated in HCT-116 p53^(+/+) human colon cancer cell line with eight derivatives displaying good activities (IC₅₀<15 μM). To characterize the molecular mechanisms involved in compound antitumoral activity, two spiropyrazoline oxindoles were selected for further studies. Both compounds were able to induce apoptosis and cell cycle arrest at G0/G1 phase and upregulated p53 steady-state levels, while decreasing its main inhibitor MDM2. Importantly, cytotoxic effects induced by spiropyrazolines oxindoles occurred in cancer cells without eliciting cell death in non-malignant CCD-18Co human colon fibroblasts. Additionally, we demonstrated that the combination of spiropyrazoline oxindole 2e with sub-toxic concentrations of the chemotherapeutic agent 5-fluorouracil (5-FU) exerted a synergistic inhibitory effect on HCT-116 colon cancer cell proliferation. Collectively, our results show the potential of spiropyrazoline oxindoles for development of novel anticancer agents.

A large-inner-diameter multi-walled carbon nanotube-based dual-drug delivery system with pH-sensitive release properties

A novel dual-drug delivery system (DDDS) for cancer chemotherapy has been established by employing highly purified and mildly oxidized large-inner-diameter multi-walled carbon nanotubes (LID-MWCNTs) as the vector. The LID-MWCNTs were modified with the antitumor drugs, cisplatin (CDDP) and doxorubicin (DOX). CDDP was encapsulated inside the nanotube vectors by a wet-chemical approach while DOX was attached to the external surfaces through non-covalently interaction. The loading efficiencies of CDDP and DOX were as high as 84.56 and 192.67%, respectively. Notably, after CDDP was encapsulated inside the nanotubes, a three-level blocking strategy, which included polyethylene glycol, folic acid and DOX, was employed to block the CDDP exits at different levels. The pH-sensitive release profile of CDDP was demonstrated using a modified characterization method, as well as that of DOX. Finally, the anticancer activity of the DDDS on MCF-7 cells was tested and a synergistic effect was recorded. This work is part of our LID-MWCNTs based drug delivery system studies, and provides a basis for developing a novel comprehensive antitumor treatment that combines chemotherapy and photothermal therapy.

Origins, Phytochemistry, Pharmacology, Analytical Methods and Safety of Cortex Moutan (Paeonia suffruticosa Andrew): A Systematic Review

Cortex Moutan (CM), a well-known traditional Chinese medicine, is commonly used for treating various diseases in China and other eastern Asian countries. Recorded in Pharmacopeias of several countries, CM is now drawing increasing attention and under extensive studies in various fields. Phytochemical studies indicate that CM contains many valuable secondary metabolites, such as monoterpene glycosides and phenols. Ample evidence from pharmacological researches suggest that CM has a wide spectrum of activities, such as anti-inflammatory, anti-oxidant, anti-tumor, anti-diabetic, cardiovascular protective, neuroprotective, hepatoprotective effects. Moreover, various analytical methods were established for the quality evaluation and safety control of CM. This review synopsizes updated information concerning the origins, phytochemistry, pharmacology, analytical method and safety of CM, aiming to provide favorable references for modern CM research and application. In conclusion, continuing pharmacological investigations concerning CM should be conducted to unravel its pharmacological mechanisms. Further researches are necessary to obtain comprehensive and applicable analytical approach for quality evaluation and establish harmonized criteria of CM.

Effects of naringin on the expression of miR-19b and cell apoptosis in human hepatocellular carcinoma

The effects of naringin on the expression of miR-19b and cell apoptosis were investigated in the human hepatocellular carcinoma cell line HepG2. HepG2 cells were treated with varied concentrations of naringin. The effects of naringin on the proliferation of HepG2 cells were observed by an MTT assay, morphological changes of cells were observed by an inverted microscope, cell apoptosis was detected by DAPI staining, miR-19b mRNA levels were determined with RT-PCR, and the expression of Bax and Bcl-2 proteins was examined by western blot assay. MTT results showed that naringin significantly inhibited the proliferation of HepG2 cells. Apoptotic HepG2 cells showed obvious changes in morphology under inverted microscope. DAPI staining suggested that naringin could induce cell shrinkage and nuclear chromatin condensation. RT-PCR results showed that naringin could upregulate the expression of miR-19b mRNA. Finally, western blot suggested that naringin upregulated the expression of Bax protein, but downregulated the expression of Bcl-2 protein. In conclusion, naringin can upregulate the expression of miR-19b mRNA and induce HepG2 cell apoptosis. In addition, it can also upregulate the expression of Bax protein and downregulate the expression of Bcl-2 protein during the process of apoptosis.

Anti-proliferative effects of paeonol on human prostate cancer cell lines DU145 and PC-3

Paeonol (Pae) is the main active ingredient from the root bark of Paeonia moutan and the grass of Radix Cynanchi Paniculati. Numerous reports indicate that Pae effectively inhibits several types of cancer lines. In this study, we report that Pae hinders prostate cancer growth both in vivo and in vitro. Human prostate cancer lines DU145 and PC-3 were cultured in the presence of Pae. The xenograft tumor in mice was established by subcutaneous injection of DU145 cells. Cell growth was measured by MTT, and the apoptosis was detected by the flow cytometry. Expression of Bcl-2, Bax, Akt, and mTOR were tested by western blotting assay. DU145 and PC-3 showed remarkable sensitivity to Pae, and exposure to Pae induced dose-and time-dependent growth inhibitory responses. Moreover, treatment of Pae promoted apoptosis and enhanced activities of caspase-3, caspase-8, and caspase-9 in DU145. Further work demonstrated Pae reduced expression of Bcl-2 and increased expression of Bax in DU145. Interestingly, we observed that Pae significantly decreased phosphorylated status of Akt and mTOR, and inhibitory effects of Pae and PI3K/Akt inhibitor on DU145 proliferation were synergistic. Finally, we confirmed that oral administration of Pae to the DU145 tumor-bearing mice significantly lowered tumor cell proliferation and led to tumor regression. Pae possesses inhibitory effects on prostate cancer cell growth both in vitro and in vivo, and the anti-proliferative effect may be closely related to its activation of extrinsic and intrinsic apoptotic pathway and inhibition of the PI3K/Akt pathway.

Proteasome Inhibitor YSY01A Enhances Cisplatin Cytotoxicity in Cisplatin-Resistant Human Ovarian Cancer Cells

Cisplatin is one of the most common drugs used for treatment of solid tumors such as ovarian cancer. Unfortunately, the development of resistance against this cytotoxic agent limits its clinical use. Here we report that YSY01A, a novel proteasome inhibitor, is capable of suppressing survival of cisplatin-resistant ovarian cancer cells by inducing apoptosis. And YSY01A treatment enhances the cytotoxicity of cisplatin in drug-resistant ovarian cancer cells. Specifically, YSY01A abrogates regulatory proteins important for cell proliferation and anti-apoptosis including NF-κB p65 and STAT3, resulting in down-regulation of Bcl-2. A dramatic increase in cisplatin uptake was also observed by inductively coupled plasma-mass spectrometry following exposure to YSY01A. Taken together, YSY01A serves as a potential candidate for further development as anticancer therapeutics targeting the proteasome.

Direct and protective effects of single or combined addition of vincristine and ε-viniferin on human HepG2 cellular oxidative stress markers in vitro

The objective of this study is to examine the direct effects of low doses and high doses of ε-viniferin, a substance known to be an antioxidant, and vincristine sulphate, a chemotherapeutic agent, alone and in combination [ε-viniferin + vincristine] on HepG2 cell strain, as well as evaluate oxidative stress after incubation periods of 3, 6, and 24 h. Direct effect was determined right after the incubation period; however, for protective effect, antioxidant protection response was determined after the treatment for 1 h with 500 μM H2O2, which is an oxidative stressor. For this purpose, superoxide dismutase was determined for enzyme activity, and lipid hydroperoxide (LPO) and reduced glutathione concentrations were studied as indicators of oxidative stress. Results show that low [3.63 µM vincristine + 3.75 µM ε-viniferin] and high [11.25 µM vincristine + 15.8 µM ε-viniferin] doses of combination groups showed similar direct antioxidant effect on LPO levels as protective when compared to the H2O2 control group (p < 0.05). Superoxide dismutase enzyme showed a direct antioxidant effect in low and high dose combination groups. In addition, when the incubation period was increased to 24 h, a protective effect was observed in both dose groups (p < 0.05). Reduced glutathione activities showed a direct effect in the low dose combination group, and a protective effect in both the low and high doses in the 24 h. These results show that combined usage of drugs in HepG2 cell strain possesses a protective effect against exogenically produced oxidative stress conditions.

The resveratrol oligomers, cis- and trans-gnetin H, from Paeonia suffruticosa seeds inhibit the growth of several human cancer cell lines

ETHNOPHARMACOLOGICAL RELEVANCE

Paeonia suffruticosa Andrews (PSE) is a well-known Chinese medicine that has been widely used as an anti-tumor, anti-oxidative and anti-inflammatory agent. cis- and trans-gnetin H are two resveratrol oligomers isolated from the seeds of PSE. Although resveratrol is widely considered to be one of the most valuable natural chemopreventive agents and there are numerous studies on the antitumor activities of resveratrol, little is known about the antitumor properties of cis- and trans-gnetin H.

MATERIALS AND METHODS

The inhibitory effects of cis- and trans-gnetin H in different human cancer cell lines were assessed using fluorescent viability tests. Cytotoxicity in human lung and breast cancer cells was detected via nuclear condensation, cell permeability, and changes in the mitochondrial membrane potential (∆ψm). Apoptosis in human lung and breast cancer cells was assessed by flow cytometry, a luminescence assay and high-content screening analysis. Finally, a xenograft mice model was used to examine the efficacy of cis-gnetin H on lung tumors.

RESULTS

cis- and trans-gnetin H have superior activity in inhibiting the proliferation of four human cancer cell lines, A549 (lung), BT20 (breast), MCF-7 (breast) and U2OS (osteosarcoma), and promote cell apoptosis, while having a minimal effect on two normal human epithelial cell lines, HPL1A (lung) and HMEC (breast) used as controls. cis- and trans-gnetin H promote apoptosis by releasing mitochondria cytochrome c, activating caspase 3/7 and inhibiting NF-κB activation. Flow cytometry analysis shows that cis- or trans-gnetin H arrested the cell cycle of cancer cells at the G0-G1 phase. Moreover, cis-gnetin H suppressed the growth of xenograft lung tumors in mice.

CONCLUSION

Collectively, our findings demonstrate the promise of the natural compounds cis- and trans-gnetin H as candidates for cancer chemotherapy agents.

Paeonol attenuates inflammation-mediated neurotoxicity and microglial activation

Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. The root of Paeonia lactiflora Pall has been considered useful for the treatment of various disorders in traditional oriental medicine. Paeonol, found in the root of Paeonia lactiflora Pall, has a wide range of pharmacological functions, including anti-oxidative, anti-inflammatory and neuroprotective activities. The objective of this study was to examine the efficacy of paeonol in the repression of inflammation-induced neurotoxicity and microglial cell activation. Organotypic hippocampal slice cultures and primary microglial cells from rat brain were stimulated with bacterial lipopolysaccharide. Paeonol pretreatment was performed for 30 minutes prior to lipopolysaccharide addition. Cell viability and nitrite (the production of nitric oxide), tumor necrosis factor-alpha and interleukin-1beta products were measured after lipopolysaccharide treatment. In organotypic hippocampal slice cultures, paeonol blocked lipopolysaccharide-related hippocampal cell death and inhibited the release of nitrite and interleukin-1beta. Paeonol was effective in inhibiting nitric oxide release from primary microglial cells. It also reduced the lipopolysaccharide-stimulated release of tumor necrosis factor-alpha and interleukin-1β from microglial cells. Paeonol possesses neuroprotective activity in a model of inflammation-induced neurotoxicity and reduces the release of neurotoxic and proinflammatory factors in activated microglial cells.

Paeonol suppresses chondrosarcoma metastasis through up-regulation of miR-141 by modulating PKCδ and c-Src signaling pathway

Chondrosarcoma, a primary malignant bone cancer, has potential for local invasion and distant metastasis, especially to the lungs. Patients diagnosed with it show poor prognosis. Paeonol (2'-hydroxy-4'-methoxyacetophenone), the main active compound of traditional Chinese remedy Paeonia lactiflora Pallas, exhibits anti-inflammatory and anti-tumor activity; whether paeonol regulates metastatic chondrosarcoma is largely unknown. Here, we find paeonol do not increase apoptosis. By contrast, at non-cytotoxic concentrations, paeonol suppresses migration and invasion of chondrosarcoma cells. We also demonstrate paeonol enhancing miR-141 expression and miR-141 inhibitor reversing paeonol-inhibited cell motility; paeonol also reduces protein kinase C (PKC)d and c-Src kinase activity. Since paeonol inhibits migration and invasion of human chondrosarcoma via up-regulation of miR-141 via PKCd and c-Src pathways, it thus might be a novel anti-metastasis agent for treatment of metastatic chondrosarcoma.

Towards novel anti-tumor strategies for hepatic cancer: ɛ-viniferin in combination with vincristine displays pharmacodynamic synergy at lower doses in HepG2 cells

Hepatocellular carcinoma is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. The efficacy of novel combination treatments are increasingly evaluated with use of integrative biology research and development (R&D) strategies and methodological triangulation. We investigated the anti-tumor effect of ɛ-viniferin alone, and the putative synergy of ɛ-viniferin with vincristine on the growth of HepG2 cells in vitro. Growth inhibition and apoptosis induction were determined by MTT assay and annexin V/propidium iodide (PI), respectively. Morphological changes and DNA fragmentation were investigated under electron microscopy and by agarose gel electrophoresis, respectively. The results collectively showed that treating cells with ɛ-viniferin and vincristine significantly inhibited cell viability at lower doses as compared to each agent applied alone. IC(50) values for ɛ-viniferin and vincristine were determined as 98.3 and 52.5 μM at 24 h, respectively. IC(50) value of ɛ-viniferin in combination with vincristine was 15.8+11.25 μM (mean/SD) at 24 h. The viability of cells treated with 17.9 μM vincristine alone for 24 h was 79.62%; it reduced to 26.53% when 25 μM ɛ-viniferin was added in combination with vincristine (p<0.05). We found that combination of drugs promoted the sensitivity of cells against to vincristine treatment. The effect of combined use was in support of a synergistic pharmacodynamic effect. Moreover, low doses of the combination regimen induced phosphatidyl re-localization, morphological changes, and DNA fragmentation, and therefore caused apoptotic death. This study thus suggests that low concentrations of ɛ-viniferin and vincristine can enhance the anti-tumor effects efficiently by inducing HepG2 cell apoptosis. Further studies in other model systems are warranted with a view to potential future applications in the clinic of such combination regimens and their putative mechanism of action in the observed synergy reported here.

The radiosensitizing effect of Paeonol on lung adenocarcinoma by augmentation of radiation-induced apoptosis and inhibition of the PI3K/Akt pathway

PURPOSE

To investigate the radiosensitizing effect and mechanism of action by the natural product Paeonol on lung adenocarcinoma both in vitro and in vivo.

MATERIALS AND METHODS

Two lung adenocarcinoma cell lines (human lung adenocarcinoma cell line A549 and mouse Lewis lung carcinoma (LLC) cell line) were chosen for this research. In order to select the experimental concentrations of Paeonol, cytotoxicity was determined using a MTT (3-[4,5-dimethylthiazol-2-yl]-2,5- diphenyltetrazolium bromide) assay. A clonogenic assay was performed to measure the radiosensitizing effects. Apoptosis was determined by the Tunel (terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling) assay and flow cytometry. Protein expression was analyzed by Western blotting. To test the radiosensitizing effect in vivo, a transplanted tumor model was established.

RESULTS

The MTT assay showed that Paeonol inhibited proliferation of cells. Paeonol concentration ranged from an IC5 (5% inhibiting concentration) to an IC20 and was used at non-toxic concentrations for subsequent experiments. The clonogenic assay showed that Paeonol enhanced the radiosensitivity of cells. Data from the Tunel assay and flow cytometry verified that Paeonol enhanced radiation-induced apoptosis. Paeonol inhibited the activation of the PI3K/AKT (Phosphatidylinositol 3-kinase/ Protein Kinase B) pathway and down-regulated the expression of COX-2 (Cyclooxygenase-2) and Survivin. Paeonol (1718 mg/kg) combined with 10 Gy irradiation inhibited the growth of a transplanted tumor model in vivo, resulting in the longest tumor growth time, tumor growth delay and the highest inhibition ratio when compared with the radiotherapy alone group.

CONCLUSIONS

It is reported for the first time that Paeonol has a radiosensitizing effect on lung adenocarcinoma both in vitro and in vivo. This effect could be related to the augmentation of radiation-induced apoptosis and the inhibition of the PI3K/Akt signalling pathway and its downstream proteins: COX-2 and Survivin.

Cortex Moutan Induces Bladder Cancer Cell Death via Apoptosis and Retards Tumor Growth in Mouse Bladders

Cortex Moutan is the root bark of Paeonia suffruticosa Andr. It is the herbal medicine widely used in Traditional Chinese Medicine for the treatment of blood-heat and blood-stasis syndrome. Furthermore, it has been reported that Cortex Moutan has anticancer effect. In this study, the Cortex Moutan extract was evaluated in bladder cancer therapy in vitro and in vivo. Cortex Moutan extract reduces cell viability with IC50 between 1~2 mg/ml in bladder cancer cells, and it has lower cytotoxicity in normal urotheliums. It arrests cells in G1 and S phase and causes phosphatidylserine expression in the outside of cell membrane. It induces caspase-8 and caspase-3 activation and poly(ADP-ribose) polymerase degradation. The pan caspase inhibitor z-VAD-fmk reverses Cortex Moutan-induced cell death. Cortex Moutan also inhibits cell invasion activity in 5637 cells. In mouse orthotopic bladder cancer model, intravesical application of Cortex Moutan decreases the bladder tumor size without altering the blood biochemical parameters. In summary, these results demonstrate the antiproliferation and anti-invasion properties of Cortex Moutan in bladder cancer cells and its antibladder tumor effect in vivo. Cortex Moutan may provide an alternative therapeutic strategy for the intravesical therapy of superficial bladder cancer.

Inhibitory effect of valproic acid on bladder cancer in combination with chemotherapeutic agents in vitro and in vivo

Histone deacetylase inhibitors (HDACIs) are a promising class of drugs that act as antiproliferative agents by promoting differentiation and inducing apoptosis. Valproic acid (VPA) is an HDACI that has been widely used as an anti-convulsant and shows promise as a chemotherapeutic drug for a number of tumor cells. The present study aimed to investigate the inhibitory effect of VPA on the viability of bladder cancer cells and its synergistic effect with chemotherapeutic agents in vitro and in vivo. The cell viability of human bladder cancer cell lines following treatment with VPA and/or VPA in combination with mitomycin C, cisplatin (DDP) and adriamycin were determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Hoechst staining was used to observe the morphology of the apoptotic cells. Survivin protein and acetylated histone H3 levels were quantified using western blot analysis. The in vivo tumor growth inhibition of VPA was determined in rats with N-methyl-N-nitrosourea-induced bladder cancer. VPA significantly inhibited the growth of the bladder cancer cells in a concentration- and time-dependent manner. Furthermore, improved results were achieved for tumor inhibition when VPA was combined with chemotherapeutic agents in vitro and in vivo. Survivin expression decreased and acetylated histone H3 expression increased in the bladder cancer cells following the treatment with VPA. Intravesical injections of VPA were able to inhibit tumor progression when combined with DDP. In conclusion, VPA acts as an HDACI that has a direct anticancer effect and markedly enhances the action of several chemotherapy agents. VPA may sensitize bladder cancer to anticancer drugs by downregulating survivin expression.

Endoplasmic reticulum stress-induced resistance to doxorubicin is reversed by paeonol treatment in human hepatocellular carcinoma cells

Background

Endoplasmic reticulum stress (ER stress) is generally activated in solid tumors and results in tumor cell anti-apoptosis and drug resistance. Paeonol (Pae, 2-hydroxy-4-methoxyacetophenone), is a natural product extracted from the root of Paeonia Suffruticosa Andrew. Although Pae displays anti-neoplastic activity and increases the efficacy of chemotherapeutic drugs in various cell lines and in animal models, studies related to the effect of Pae on ER stress–induced resistance to chemotherapeutic agents in hepatocellular carcinoma (HCC) are poorly understood.

Methodology/Principal Findings

In this study, we investigated the effect of the endoplasmic reticulum (ER) stress response during resistance of human hepatocellular carcinoma cells to doxorubicin. Treatment with the ER stress-inducer tunicamycin (TM) before the addition of doxorubicin reduced the rate of apoptosis induced by doxorubicin. Interestingly, co-pretreatment with tunicamycin and Pae significantly increased apoptosis induced by doxorubicin. Furthermore, induction of ER stress resulted in increasing expression of COX-2 concomitant with inactivation of Akt and up-regulation of the pro-apoptotic transcription factor CHOP (GADD153) in HepG2 cells. These cellular changes in gene expression and Akt activation may be an important resistance mechanism against doxorubicin in hepatocellular carcinoma cells undergoing ER stress. However, co-pretreatment with tunicamycin and Pae decreased the expression of COX-2 and levels of activation of Akt as well as increasing the levels of CHOP in HCC cells.

Conclusions/Significance

Our results demonstrate that Pae reverses ER stress–induced resistance to doxorubicin in human hepatocellular carcinoma cells by targeting COX-2 mediated inactivation of PI3K/AKT/CHOP.

Azithromycin synergistically enhances anti-proliferative activity of vincristine in cervical and gastric cancer cells

In this study, the anti-proliferative and anticancer activity of azithromycin (AZM) was examined. In the presence of AZM, cell growth was inhibited more effectively in Hela and SGC-7901 cancer cells, relative to transformed BHK-21 cells. The respective 50% inhibition of cell growth (IC₅₀) values for Hela, SGC-7901 and BHK-21 were 15.66, 26.05 and 91.00 µg/mL at 72 h post incubation, indicative of a selective cytotoxicity against cancer cells. Cell apoptosis analysis using Hoechst nuclear staining and annexin V-FITC binding assay further demonstrated that AZM was capable of inducing apoptosis in both cancer cells and transformed cells. The apoptosis induced by AZM was partly through a caspase-dependent mechanism with an up-regulation of apoptotic protein cleavage PARP and caspase-3 products, as well as a down-regulation of anti-apoptotic proteins, Mcl-1, bcl-2 and bcl-X1. More importantly, a combination of AZM and a low dose of the common anti-cancer chemotherapeutic agent vincristine (VCR), produced a selectively synergistic effect on apoptosis of Hela and SGC-7901 cells, but not BHK-21 cells. In the presence of 12.50 μg/mL of VCR, the respective IC₅₀ values of Hela, SGC-7901 and BHK-21 cells to AZM were reduced to 9.47 µg/mL, 8.43 µg/mL and 40.15 µg/mL at 72 h after the incubation, suggesting that the cytotoxicity of AZM had a selective anti-cancer effect on cancer over transformed cells in vitro. These results imply that AZM may be a potential anticancer agent for use in chemotherapy regimens, and it may minimize side effects via reduction of dosage and enhancing the effectiveness common chemotherapeutic drugs.

Aqueous Extract of Paeonia suffruticosa Inhibits Migration and Metastasis of Renal Cell Carcinoma Cells via Suppressing VEGFR-3 Pathway

Renal cell carcinoma (RCC) cells are characterized by strong drug resistance and high metastatic incidence. In this study, the effects of ten kinds of Chinese herbs on RCC cell migration and proliferation were examined. Aqueous extract of Paeonia suffruticosa (PS-A) exerted strong inhibitory effects on cancer cell migration, mobility, and invasion. The results of mouse xenograft experiments showed that the treatment of PS-A significantly suppressed tumor growth and pulmonary metastasis. We further found that PS-A markedly decreased expression of VEGF receptor-3 (VEGFR-3) and phosphorylation of FAK in RCC cells. Moreover, the activation of Rac-1, a modulator of cytoskeletal dynamics, was remarkably reduced by PS-A. Additionally, PS-A suppressed polymerization of actin filament as demonstrated by confocal microscopy analysis and decreased the ratio of F-actin to G-actin in RCC cells, suggesting that PS-A inhibits RCC cell migration through modulating VEGFR-3/FAK/Rac-1 pathway to disrupt actin filament polymerization. In conclusion, this research elucidates the effects and molecular mechanism for antimigration of PS-A on RCC cells and suggests PS-A to be a therapeutic or adjuvant strategy for the patients with aggressive RCC.

Paeonol inhibits tumor growth in gastric cancer in vitro and in vivo

AIM: To investigate the anti-tumor effects of paeonol in gastric cancer cell proliferation and apoptosis in vitro and in vivo.

METHODS: Murine gastric cancer cell line mouse forestomach carcinoma (MFC) or human gastric cancer cell line SGC-7901 was cultured in the presence or absence of paeonol. Cell proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and cell cycle and apoptosis by flow cytometry and TUNEL staining. Tumor growth after subcutaneous implantation of MFC cells in mice was monitored, and the effects of treatment with paeonol were determined.

RESULTS: In vitro, paeonol caused dose-dependent inhibition on cell proliferation and induced apoptosis. Cell cycle analysis revealed a decreased proportion of cells in G0/G1 phase, with arrest at S. Paeonol treatment in gastric cancer cell line MFC and SGC-790 cells significantly reduced the expression of Bcl-2 and increased the expression of Bax in a concentration-related manner. Administration of paeonol to MFC tumor-bearing mice significantly lowered the tumor growth and caused tumor regression.

CONCLUSION: Paeonol has significantly growth-inhibitory and apoptosis-inducing effects in gastric cancer cells both in vitro and in vivo.

Selection of cytotoxicity markers for the screening of new chemical entities in a pharmaceutical context: a preliminary study using a multiplexing approach

The present study was undertaken to validate a battery of cytotoxicity assays performed in a multiplex format to screen pharmaceutical compounds at an early stage of drug development. Two experiments were performed on HepG2 cells and the parameters were measured in 96-well plates. Biological and technical triplicates were performed to evaluate the reproducibility of the assay. In the first experiment, HepG2 cells were exposed to tamoxifen, staurosporine, phenobarbital and triton X-100 for 2 and 24h. The following nine cytotoxicity parameters were analyzed, cell viability, lactate dehydrogenase (LDH), adenosine triphosphate (ATP), caspase-3/7, aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and alpha-glutathione-S-transferase (alpha-GST). In the second experiment, HepG2 cells were exposed to doxorubicin, t-butyl hydroperoxide, ferrous sulfate and sulfamoxole for 2 and 24h. Based on the results of the first experiment, six cytotoxicity parameters were selected for further evaluation (cell viability, ATP, LDH, caspase, AST and GLDH). ALT (activity always below detection limit), ALP (no response to drug treatment) and alpha-GST (too labor intensive and not possible to multiplex) were eliminated. The analysis of the data revealed that the reproducibility of the assays was accurate according to principal component analysis. Our data also clearly indicated that the potential of this battery of selected assays measured in a multiplex format not only made it possible to rank and select the most promising drug candidates based on their cytotoxic potential, but also to gather information that may help to understand some of the toxic events occurring in the cells.

Chinese herbal medicine (Tuhuai extract) exhibits topical anti-proliferative and anti-inflammatory activity in murine disease models

While psoriasis is one of the most common skin disorders in humans, effective, safe and inexpensive treatments are still largely unavailable. Chinese herbal medicine (CHM) has been used for centuries for treating psoriasis and several reports claim that systemic administration of one such CHM, Tuhuai, mainly composed of flos sophorae, smilax glabra roxb and licorice, is effective in psoriasis. However, the mechanisms by which this CHM improves psoriasis are not yet clear. Two universal features of psoriasis are epidermal hyperplasia and inflammation. Moreover, drugs that specifically inhibit epidermal hyperplasia and/or inflammation are widely used to treat psoriasis. Here, we investigated whether topical applications of Tuhuai extract exhibit anti-proliferative and anti-inflammatory activities in two murine models of inflammatory dermatoses. To assess Tuhuai's potential anti-proliferative effect, we disrupted epidermal barrier function twice-daily for 4 days in normal hairless mice followed by topical applications of either 1% Tuhuai extract or Vehicle to both flanks immediately after each barrier perturbation. Changes in epidermal proliferation and apoptosis were evaluated by immunohistochemistry and TUNEL staining. To assess the anti-inflammatory effects of Tuhuai, both irritant (phorbol ester) and acute allergic contact dermatitis (oxazolone) models were used. Whereas topical Tuhuai extract did not alter epidermal proliferation or induce irritation in normal skin, it both reduced epidermal hyperplasia in the epidermal hyperproliferative model, and reduced inflammation in both irritant and allergic contact dermatitis models. As topical Tuhuai extract exhibits anti-proliferative and anti-inflammatory properties in a variety of human models of inflammatory dermatoses, Tuhuai could provide an effective, relatively safe and inexpensive therapeutic alternative for the treatment of inflammatory dermatoses, including psoriasis.

Synergistic effect of paeonol and cisplatin on oesophageal cancer cell lines

BACKGROUND/AIM

Paeonol, a phenolic component from the root bark of Paeonia moutan, has shown great promise in antitumour activities in our previous studies. The present study was designed to investigate whether paeonol has synergistic effect with cisplatin on the growth-inhibitory of human oesophageal cancer cell lines and the possible mechanism.

METHODS

Cell viability was measured by MTT assay. Drug-drug interactions were analysed by the coefficient of drug interaction. Apoptosis was detected by acridine orange fluorescence staining and flow cytometry assay. Bcl-2, Bax and caspase-3 expression was assayed by immunohistochemical staining.

RESULTS

A synergistic inhibitory effect on viability of the two cell lines was observed after combination of paeonol with various concentrations of cisplatin. Further study showed the combination induced greater apoptosis than the groups treated with paeonol or cisplatin alone. The expression of Bcl-2 was decreased and that of Bax was increased in treatment groups, especially in the combination group, with the ratio of Bcl-2/Bax decreased correspondingly. And the combination also resulted in greater activation of caspase-3 than did either agent alone.

CONCLUSIONS

Paeonol, in combination with cisplatin, had a significantly synergistic growth-inhibitory effect on oesophageal cell line, which may be related to apoptosis induction.

Antiproliferation and apoptosis induction of paeonol in human esophageal cancer cell lines

The incidence of esophageal cancer (EC), especially adenocarcinoma, has increased tremendously in Western countries and the prognosis of EC remains poor. Paeonol (Pae), a phenolic component from the root bark of Paeonia moutan, possesses antitumor effects in vitro and in vivo. The present study showed that Pae had an antiproliferative effect on the two human EC cell lines (SEG-1 and Eca-109), with different sensitivities to Pae. Acridine orange staining and flow cytometry assays showed that Pae induced apoptosis on the two cell lines. Further analyses indicated that Pae resulted in a cell cycle arrest at S-phase. Immunohistochemical staining showed the expression of Bcl-2 was decreased and that of Bax was increased in treatment groups, with the ratio of Bcl-2/Bax decreased correspondingly. The results show that Pae shows growth inhibitory and apoptosis induction property and may be a promising agent for the EC treatment.

Paeonol inhibits RANKL-induced osteoclastogenesis by inhibiting ERK, p38 and NF-kappaB pathway

Numerous studies have indicated that inflammatory cytokines play a major role in osteoclastogenesis, leading to the bone resorption that is frequently associated with osteoporosis. Paeonol (2'-hydroxy-4'-methoxyacetophenone), the main active compound of the traditionally used Chinese herb Paeonia lactiflora Pallas, has anti-inflammatory activity. Here we found that paeonol markedly inhibited the receptor activator of nuclear factor kappa B ligand (RANKL) plus macrophage colony stimulating factor (M-CSF)-induced osteoclastic differentiation from bone marrow stromal cells and RAW264.7 macrophage cells. In addition, in an assay of osteoclast activity on substrate plates, paeonol significantly decreased the resorption activity of mature osteoclasts. Treatment of RAW264.7 macrophages with RANKL induced extracellular signal-regulated kinases (ERK), p38 and c-Jun N-terminal kinase (JNK) phosphorylation. However, RANKL-induced ERK, p38 but not JNK phosphorylation was attenuated by paeonol. Furthermore, RANKL-mediated increase of IkappaBalpha phosphorylation, p65 phosphorylation at Ser(536), kappaB-luciferase activity and NF-kappaB binding activity was inhibited by paeonol. In addition, paeonol also prevented the bone loss inducing by ovariectomy in vivo. Our data suggest that paeonol inhibits osteoclastogenesis from bone marrow stromal cells and macrophage cells via attenuated of RANKL-induced ERK, p38 and NF-kappaB activation, which in turn protect bone loss from ovariectomy.