Psoralidin, a coumestan analogue, as a novel potent estrogen receptor signaling molecule isolated from Psoralea corylifolia

In silico analysis, isolation, and cytotoxicity evaluation of the coumestans from Cullen corylifolium (L.) Medik

Cullen corylifolium is well known for diverse phytoconstituents that possess multifaceted pharmacology, and one such less explored class is coumestans, which have not been well explored for their anticancer activities. One of the popular cancer targets is the Epidermal Growth Factor Receptor, a tyrosine kinase involved in various cancers, especially breast and lung cancer hence, a crucial cancer target. This work is focussed on molecular docking and molecular simulation studies on coumestans against EGFR. The rigorous docking studies resulted in two coumestans (1 and 5) with binding energy less than Gefitinib and Erlotinib. Compounds 1 and 5 were subjected to molecular simulation, binding free energy calculation, per-residue energy decomposition, and in silico ADMET prediction. The best hit, compound 1 was evaluated for its cytotoxicity against MDA-MB-231 and A549 cells via in vitro assay. The ligand-protein complex exhibited good stability, binding free energies, better in silico pharmacokinetics, low toxicity, and good cytotoxicity.

Effects of psoralidin on the expression of glutamate decarboxylases and inhibitory synapse development

Gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter required for excitation/inhibition balance is synthesized by the glutamic acid decarboxylases (GADs) in GABAergic neurons. The levels and activity of GADs are strongly correlated with GABA and neural transmission. Dysregulation of GADs and GABA is associated with various neurological disorders. The study used psoralidin, found in the seeds of Psoralea corylifolia, to investigate its effect on GAD levels and regulatory mechanisms in primary cortical neurons. Psoralidin reduced GAD67 through transcriptional regulation. The reduction was not mediated by the N-methyl-D-aspartate receptor. Additionally, psoralidin attenuated the formation of inhibitory synapses in primary hippocampal neurons.

Multi-technology integrated network pharmacology-based study on phytochemicals, active metabolites, and molecular mechanism of Psoraleae Fructus to promote melanogenesis

ETHNOPHARMACOLOGICAL RELEVANCE

According to the Compendium of Materia Medica (Shizhen Li, Ming dynasty) and Welfare Pharmacy (Song dynasty), Psoraleae Fructus (PF), a traditional Chinese medicine (TCM) has a bitter taste and warm nature, which has the effect of treating spleen and kidney deficiency and skin disease. Although PF has been widely used since ancient times and has shown satisfactory efficacy in treating vitiligo, the active substances and the mechanism of PF in promoting melanogenesis remain unclear.

AIM OF THE STUDY

To explore the active substances and action mechanisms of PF in promoting melanogenesis.

MATERIALS AND METHODS

Firstly, UPLC-UV-Q-TOF/MS was used to characterize the components in PF extract and identify the absorption components and metabolites of PF after oral administration at usual doses in rats. Secondly, the active substances and related targets and pathways were predicted by network pharmacology and molecular docking. Finally, pharmacodynamic and molecular biology experiments were used to verify the prediction results.

RESULTS

The experimental results showed that 15 compounds were identified in PF extract, and 44 compounds, consisting of 8 prototype components and 36 metabolites (including isomers) were identified in rats' plasma. Promising action targets (MAPK1, MAPK8, MAPK14) and signaling pathways (MAPK signaling pathway) were screened and refined to elucidate the mechanism of PF against vitiligo based on network pharmacology. Bergaptol and xanthotol (the main metabolites of PF), psoralen (prototype drug), and PF extract significantly increased melanin production in zebrafish embryos. Furthermore, bergaptol could promote the pigmentation of zebrafish embryos more than psoralen and PF extract. Bergaptol significantly increased the protein expression levels of p-P38 and decreased ERK phosphorylation in B16F10 cells, which was also supported by the corresponding inhibitor/activator combination study. Moreover, bergaptol increased the mRNA expression levels of the downstream microphthalmia-associated transcription factor (MITF) and tyrosinase in B16F10 cells. Our data elucidate that bergaptol may promote melanogenesis by regulating the p-P38 and p-ERK signaling pathway.

CONCLUSIONS

This study will lay a foundation for discovering potential new drugs for treating vitiligo and provide feasible ideas for exploring the mechanism of traditional Chinese medicine.

Unveiling hepatotoxicity distinction of coumarin-related compounds from glycosides to aglycones in Fructus Psoraleae by integrating UPLC-Q-TOF-MS and high content analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Fructus Psoraleae (FP), the dried and ripe fruit of Cullen corylifolium (L.) Medik., is widely used due to its various clinical pharmacological effects, but its hepatotoxicity restricts its clinical application. So far, its hepatotoxic components and their underlying mechanism have not been systematically elucidated.

AIM OF THE STUDY

This study was undertaken to reveal the hepatotoxicity distinction of coumarin-related compounds from glycosides to aglycones in FP and elucidate their potential mechanism.

METHODS

Rats were administrated with the aqueous extract of Fructus Psoraleae (AEFP), in which eight coumarin-related compounds were focused. Subsequently, compounds exposed in rats' livers were detected by UPLC-Q-TOF-MS, and the identified hepatotoxic compounds were evaluated to elaborate their possible mechanism by the aid of high content analysis (HCA).

RESULTS

Eight coumarin-related compounds were identified, among which psoralenoside (PO), isopsoralenoside (IPO), psoralen (P), and isopsoralen (IP) were the principally exposed compounds in rats' livers. Furocoumarinic acid glucoside (FAG), (E)-3-(4-(((2S, 3R, 4S, 5S, 6R)-3,4,5-trihydroxy-6-(hydroxymethyl) tetrahydro-2H-pyran-2-yl) oxy) benzofuran-5-yl) acrylic acid (isofurocoumarinic acid glucoside, IFAG), furocoumarinic acid (FA), and (E)-3-(4-hydroxybenzofuran-5-yl) acrylic acid (isofurocoumarinic acid, IFA) were also detected in low abundance. P, IP, FA, and IFA were identified as the hepatotoxic compounds, while their glycosides were almost non-hepatotoxic. The HCA's results showed that hepatotoxic compounds disrupted the balance in reactive oxygen species (ROS), nuclear area, and mitochondrial membrane potential of HepG2 cells, leading to the occurrence of hepatotoxicity.

CONCLUSIONS

P, IP, FA, and IFA were identified as hepatotoxic compounds, from which P and IP were proposed as the important risk components for hepatotoxicity. The conversion from glycosides to aglycones played an essential role in FP-induced hepatotoxicity.

Estrogenic flavonoids and their molecular mechanisms of action

Flavonoids are a major group of phytoestrogens associated with physiological effects, and ecological and social impacts. Although the estrogenic activity of flavonoids was reported by researchers in the fields of medical, environmental and food studies, their molecular mechanisms of action have not been comprehensively reviewed. The estrogenic activity of the respective classes of flavonoids, anthocyanidins/anthocyanins, 2-arylbenzofurans/3-arylcoumarins/α-methyldeoxybenzoins, aurones/chalcones/dihydrochalcones, coumaronochromones, coumestans, flavans/flavan-3-ols/flavan-4-ols, flavanones/dihydroflavonols, flavones/flavonols, homoisoflavonoids, isoflavans, isoflavanones, isoflavenes, isoflavones, neoflavonoids, oligoflavonoids, pterocarpans/pterocarpenes, and rotenone/rotenoids, was summarized through a comprehensive literature search, and their structure-activity relationship, biological activities, signaling pathways, and applications were discussed. Although the respective classes of flavonoids contained at least one chemical mimicking estrogen, the mechanisms varied, such as those with estrogenic, anti-estrogenic, non-estrogenic, and biphasic activities, and additional activities through crosstalk/bypassing, which exert biological activities through cell signaling pathways. Such mechanistic variations of estrogen action are not limited to flavonoids and are observed among other broad categories of chemicals, thus this group of chemicals can be termed as the "estrogenome". This review article focuses on the connection of estrogen action mainly between the outer and the inner environments, which represent variations of chemicals and biological activities/signaling pathways, respectively, and form the basis to understand their applications. The applications of chemicals will markedly progress due to emerging technologies, such as artificial intelligence for precision medicine, which is also true of the study of the estrogenome including estrogenic flavonoids.

Plant Coumarins with Anti-HIV Activity: Isolation and Mechanisms of Action

This review summarizes and systematizes the literature on the anti-HIV activity of plant coumarins with emphasis on isolation and the mechanism of their antiviral action. This review summarizes the information on the anti-HIV properties of simple coumarins as well as annulated furano- and pyranocoumarins and shows that coumarins of plant origin can act by several mechanisms: inhibition of HIV reverse transcriptase and integrase, inhibition of cellular factors that regulate HIV-1 replication, and transmission of viral particles from infected macrophages to healthy ones. It is important to note that some pyranocoumarins are able to act through several mechanisms or bind to several sites, which ensures the resistance of these compounds to HIV mutations. Here we review the last two decades of research on the anti-HIV activity of naturally occurring coumarins.

Combination of molecular docking and liver transcription sequencing analysis for the evaluation of salt-processed psoraleae fructus-induced hepatotoxicity in ovariectomized mice

ETHNOPHARMACOLOGICAL RELEVANCE

Salt-processed Psoraleae fructus (SPF) is widely used as a phytoestrogen-like agent in the treatment of osteoporosis. However, SPF-associated hepatotoxicity is a known health hazard. Cholestasis is often associated with SPF-induced hepatotoxicity. Notably, clinical liver injury is a common side effect of SPF in the treatment of osteoporosis; however, the exact mechanism underlying this phenomenon is unclear.

AIM OF THE STUDY

To evaluate SPF-induced hepatotoxicity in an ovariectomized murine model of estrogen deficiency and examine the mechanisms underlying this process.

MATERIALS AND METHODS

To explore the molecular mechanism of SPF-induced cholestatic liver injury, different concentrations of SPF (5 and 10 g/kg) were intragastrically administered to ovariectomized and non-ovariectomized female ICR mice for 30 days.

RESULTS

SPF-treated mice showed noticeably swollen hepatocytes, dilated bile ducts, and elevated levels of serum biochemical markers. Compared to ovariectomized mice, these changes were more prominent in non-ovariectomized mice. According to the sequence data, a total of 6689 mRNAs were identified. Compared with the control group, 1814 differentially expressed mRNAs were identified in the group treated with high SPF doses (SPHD), including 939 upregulated and 875 downregulated mRNAs. Molecular docking and Western blot experiments showed that liver injury was closely related to the estrogen levels. Compared with the negative control group, the expression levels of FXR, Mrp2, CYP7a1, BSEP, SULT1E1, HNF4a, and Nrf2 decreased in the estradiol-treated (E2), low-dose SPF-treated (SPLD), and SPHD groups. Interestingly, the expression levels of FXR, CYP7a1, SULT1E1, and HNF4α were significantly higher in the ovariectomized groups than in the non-ovariectomized groups (#P < 0.05; ###P < 0.001).

CONCLUSIONS

Overall, this study demonstrates that SPF downregulates key enzymes involved in cholesterol and bile acid biosyntheses, posing a risk for cholestatic liver injury. SPF also regulates the FXR-SULT1E signaling pathway via HNF4α, which is an important causative factor of cholestasis. Moreover, the severity of liver damage was significantly lower in the ovariectomized groups than in the non-ovariectomized group. These results suggest that the estrogen level is the most critical factor determining liver injury.

Synthesis of Phenolic Coumestans via a Sequential Dehydrogenation/Oxa-Michael Addition Reaction of 2',4'-Dihydroxyl-3-arylcoumarins

A facile and practical approach for the synthesis of natural coumestans and derivatives starting from 2',4'-dihydroxyl-3-arylcoumarins has been developed. The process involved a seqential intramolecular dehydrogenation/oxa-Micheal reaction efficiently promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene at 40 °C under metal- and ligand-free conditions with good functional group compatibility.

Plants in Anticancer Drug Discovery: From Molecular Mechanism to Chemoprevention

Cancer is one of the primary causes of mortality globally, and the discovery of new anticancer drugs is the most important need in recent times. Natural products have been recognized as effective in fight against various diseases including cancer for over 50 years. Plants and microbes are the primary and potential sources of natural compounds to fight against cancer. Moreover, researches in the field of plant-based natural compounds have moved towards advanced and molecular level understandings from the last few decades, leading to the development of potent anticancer agents. Also, plants have been accepted as abundant and prosperous sources for the development of novel therapeutic agents for the management and prevention of different cancer types. The high toxicity of some cancer chemotherapy drugs, as well as their unfavorable side effects and drugs resistance, drives up the demand for natural compounds as new anticancer drugs. In this detailed evidence-based mechanistic review, facts and information about various medicinal plants, their bioactive compounds with their potent anticancer activities against different cancers have been gathered, with further approach to represent the molecular mechanism behind the anticancer activity of these plants. This review will be beneficial for investigators/scientists globally involved in the development of natural, safe, effective, and economical therapeutic agents/drugs against various cancers. This might be an important contribution in the field of drug discovery, where drugs can be used alone or in combination to increase the efficacy of newly synthesized drugs.

A review of alpha-glucosidase inhibitors from plants as potential candidates for the treatment of type-2 diabetes

Diabetes mellitus is a multifactorial global health disorder that is rising at an alarming rate. Cardiovascular diseases, kidney damage and neuropathy are the main cause of high mortality rates among individuals with diabetes. One effective therapeutic approach for controlling hyperglycemia associated with type-2 diabetes is to target alpha-amylase and alpha-glucosidase, enzymes that catalyzes starch hydrolysis in the intestine. At present, approved inhibitors for these enzymes are restricted to acarbose, miglitol and voglibose. Although these inhibitors retard glucose absorption, undesirable gastrointestinal side effects impede their application. Therefore, research efforts continue to seek novel inhibitors with improved efficacy and minimal side effects. Natural products of plant origin have been a valuable source of therapeutic agents with lesser toxicity and side effects. The anti-diabetic potential through alpha-glucosidase inhibition of plant-derived molecules are summarized in this review. Eight molecules (Taxumariene F, Akebonoic acid, Morusin, Rhaponticin, Procyanidin A2, Alaternin, Mulberrofuran K and Psoralidin) were selected as promising drug candidates and their pharmacokinetic properties and toxicity were discussed where available.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11101-021-09773-1.

A new strategy for discovering effective substances and mechanisms of traditional Chinese medicine based on standardized drug containing plasma and the absorbed ingredients composition, a case study of Xian-Ling-Gu-Bao capsules

ETHNOPHARMACOLOGICAL RELEVANCE

The overall therapeutic effect of traditional Chinese medicine formulae (TCMF) was achieved by the interactions of multiple components with multiple targets. However, current pharmacology research strategies have struggled to identify effective substance groups and encountered challenges in elucidating the underlying mechanisms of TCMF.

AIM

In this study, a comprehensive strategy was proposed and applied to elucidate the interactions of the multiple components that underlie the functions of the famous TCMF: Xian-Ling-Gu-Bao (XLGB) capsule on bone metabolism in vivo and to elucidate the molecular mechanisms underlying the effects of XLGB on bone cells, especially on osteoblasts.

METHODS

The efficacy of XLGB in the protection against bones loss in ovariectomized (OVX) rats was confirmed by Micro-CT analysis. The anti-osteoporosis mechanism involved in the systemic regulatory actions of XLGB was elucidated by transcriptome sequencing analysis on bone marrow mesenchymal stem cells isolated from OVX rats. Moreover, the components absorbed in XLGB-treated plasma were characterized by mass spectrometry analysis, and subsequently, a standardized preparation process of drug-containing plasma was established. The synergistic osteogenic effect of the multiple components in plasma was investigated by a combination and then knockout of components using pre-osteoblast MC3T3-E1 cells. In order to decipher the underlying mechanism of XLGB, the targets of the absorbed components on bone were predicted by target prediction and network pharmacology analysis, then several interactions were validated by biochemical and cell-based assay.

RESULTS

A total of 18 genes, including HDC, CXCL1/2, TNF, IL6 and Il1b, were newly found to be the major target genes regulated by XLGB. Interestingly, we found that a combination of the three absorbed components, i.e. MSP, rather than their single form at the same concentration, stimulated the formation of calcified nodules in MC3T3-E1 cells, suggesting a synergistic effect of these components. Besides, target prediction and experimental validation confirmed the binding affinity of corylin and icaritin for estrogen receptor α and β, the inhibitory activity of isobavachin and isobavachalcone on glycogen synthase kinase-3β, and the inhibitory activity of isobavachalcone on cathepsin K. The cell-based assay further confirmed the result of the biochemical assay. A network that integrated absorbed components of XLGB-targets-perturbation genes-pathways against osteoporosis was established.

CONCLUSION

Our current study provides a new systemic strategy for discovering active ingredient groups of TCM formulae and understanding their underlying mechanisms.

Induction of G2/M Cell Cycle Arrest via p38/p21Waf1/Cip1-Dependent Signaling Pathway Activation by Bavachinin in Non-Small-Cell Lung Cancer Cells

Lung cancer is the most commonly diagnosed malignant cancer in the world. Non-small-cell lung cancer (NSCLC) is the major category of lung cancer. Although effective therapies have been administered, for improving the NSCLC patient’s survival, the incident rate is still high. Therefore, searching for a good strategy for preventing NSCLC is urgent. Traditional Chinese medicine (TCM) are brilliant materials for cancer chemoprevention, because of their high biological safety and low cost. Bavachinin, which is an active flavanone of Proralea corylifolia L., possesses anti-inflammation, anti-angiogenesis, and anti-cancer activities. The present study’s aim was to evaluate the anti-cancer activity of bavachinin on NSCLC, and its regulating molecular mechanisms. The results exhibited that a dose-dependent decrease in the cell viability and colony formation capacity of three NSCLC cell lines, by bavachinin, were through G2/M cell cycle arrest induction. Meanwhile, the expression of the G2/M cell cycle regulators, such as cyclin B, p-cdc2^Y15, p-cdc2^T161, and p-wee1, was suppressed. With the dramatic up-regulation of the cyclin-dependent kinase inhibitor, p21^Waf1/Cip1, the expression and association of p21^Waf1/Cip1 with the cyclin B/cdc2 complex was observed. Silencing the p21^Waf1/Cip1 expression significantly rescued bavachinin-induced G2/M cell accumulation. Furthermore, the expression of p21^Waf1/Cip1 mRNA was up-regulated in bavachinin-treated NSCLC cells. In addition, MAPK and AKT signaling were activated in bavachinin-added NSCLC cells. Interestingly, bavachinin-induced p21^Waf1/Cip1 expression was repressed after restraint p38 MAPK activation. The inhibition of p38 MAPK activation reversed bavachinin-induced p21^Waf1/Cip1 mRNA expression and G2/M cell cycle arrest. Collectively, bavachinin-induced G2/M cell cycle arrest was through the p38 MAPK-mediated p21^Waf1/Cip1-dependent signaling pathway in the NSCLC cells.

The Potential Effects of Phytoestrogens: The Role in Neuroprotection

Phytoestrogens are naturally occurring non-steroidal phenolic plant compounds. Their structure is similar to 17-β-estradiol, the main female sex hormone. This review offers a concise summary of the current literature on several potential health benefits of phytoestrogens, mainly their neuroprotective effect. Phytoestrogens lower the risk of menopausal symptoms and osteoporosis, as well as cardiovascular disease. They also reduce the risk of brain disease. The effects of phytoestrogens and their derivatives on cancer are mainly due to the inhibition of estrogen synthesis and metabolism, leading to antiangiogenic, antimetastatic, and epigenetic effects. The brain controls the secretion of estrogen (hypothalamus-pituitary-gonads axis). However, it has not been unequivocally established whether estrogen therapy has a neuroprotective effect on brain function. The neuroprotective effects of phytoestrogens seem to be related to both their antioxidant properties and interaction with the estrogen receptor. The possible effects of phytoestrogens on the thyroid cause some concern; nevertheless, generally, no serious side effects have been reported, and these compounds can be recommended as health-promoting food components or supplements.

Naturally occurring coumestans from plants, their biological activities and therapeutic effects on human diseases

Naturally occurring coumestans are known as a collection of plant-derived polycyclic aromatic secondary metabolites which are characterized by the presence of an oxygen heterocyclic four-ring system comprising a coumarin moiety and a benzofuran moiety sharing a C˭C bond. Recently, there is an increasing attention in excavating the medicinal potential of coumestans, particularly coumestrol, wedelolactone, psoralidin and glycyrol, in a variety of diseases. This review is a comprehensive inventory of the chemical structures of coumestans isolated from various plant sources during the period of 1956-2020, together with their reported biological activities. 120 molecules were collected and further classified as coumestans containing core skeleton, dimethylpyranocoumestans, furanocoumestans, O-glycosylated coumestans and others, which showed a wide range of pharmacological activities including estrogenic, anti-cancer, anti-inflammatory, anti-osteoporotic, organ protective, neuroprotective, anti-diabetic and anti-obesity, antimicrobial, immunosuppressive, antioxidant and skin-protective activities. Furthermore, this review focuses on the counteraction of coumestans against bone diseases and organ damages, and the involved molecular mechanisms, which could provide important information to better understand the medicinal values of these compounds. This review is intended to be instructive for the rational design and development of less toxic and more effective drugs with a coumestan scaffold.

4-Chloro-3-formylcoumarin as a multifaceted building block for the development of various bio-active substituted and fused coumarin heterocycles: a brief review

This review presents the diverse synthesis of 3,4-substituted coumarins and 5-, 6- and 7-membered ring fused coumarins using 4-chloro-3-formylcoumarin as the precursor via classical reactions including metal-catalyzed and green reaction protocols.

A review: Biologically active 3,4-heterocycle-fused coumarins

The combination of heterocycles offers a new opportunity to create novel multicyclic compounds having improved biological activity. Coumarins are ubiquitous natural heterocycle widely adopted in the design of various biologically active compounds. Fusing different heterocycles with coumarin ring is one of the interesting approaches to generating novel hybrid molecules having highlighted biological activities. In the efforts to develop heterocyclic-fused coumarins, a wide range of 3,4-heterocycle-fused coumarins have been introduced bearing outstanding biological activity. The effect of heterocycles annulation at 3,4-positions of coumarin ring on the biological activity of the target structures were discussed. This review focuses on the important progress of 3,4-heterocycle-fused coumarins providing better insight for medicinal chemists on the design and preparation of biologically active heterocycle-fused coumarins with a significant therapeutic effect in the future.

Pharmacological Activities of Psoralidin: A Comprehensive Review of the Molecular Mechanisms of Action

Analysis of the most relevant studies on the pharmacological properties and molecular mechanisms of psoralidin, a bioactive compound from the seeds of Cullen corylifolium (L.) Medik. confirmed its complex therapeutic potential. In the last years, the interest of the scientific community regarding psoralidin increased, especially after the discovery of its benefits in estrogen-related diseases and as a chemopreventive agent. Growing preclinical pieces of evidence indicate that psoralidin has anticancer, antiosteoporotic, anti-inflammatory, anti-vitiligo, antibacterial, antiviral, and antidepressant-like effects. Here, we provide a comprehensive and critical review of psoralidin on its bioavailability, pharmacological activities with focus on molecular mechanisms and cell signaling pathways. In this review, we conducted literature research on the PubMed database using the following keywords: “Psoralidin” or “therapeutic effects” or “biological activity” or “Cullen corylifolium” in order to identify relevant studies regarding PSO bioavailability and mechanisms of therapeutic effects in different diseases based on preclinical, experimental studies. In the light of psoralidin beneficial actions for human health, this paper gathers complete information on its pharmacotherapeutic effects and opens new natural therapeutic perspectives in chronic diseases.

Establishment of a UPLC-MS/MS Method for Studying the Effect of Salt-Processing on Tissue Distribution of Twelve Major Bioactive Components of Qing'e Pills in Rats

Qing'e pills is clinically used for treating osteoporosis in postmenopausal women in China. Eucommiae Cortex and Psoraleae Fructus are the main herbs of Qing'e pills and are both required to be salt-processed. In order to study the influence of salt-processing on the tissue distribution of Qing'e pills, a UPLC-MS/MS method was established for studying the tissue distribution of 12 main bioactive ingredients of Qing'e pills in rats. The linear relationships of the 12 compounds in each tissue were good. The method was fully validated for its selectivity, accuracy, precision, stability, matrix effect, and extraction recovery. Then, the validated method was successfully applied for simultaneous determination of the 12 chemical components in Qing'e pills in tissues for the first time. Areas under the curve (AUC) results showed that, except for pinoresinol diglucoside, psoralen, and isopsoralen, the distribution of the other components was increased in the kidney, uterus, ovary, and testes. Relative targeting efficiency (RTE) results showed that all 12 chemical components targeted the kidney and sexual organs. The results indicated that the Eucommiae Cortex and Psoraleae Fructus after salt-processing could significantly increase the distribution of components to the kidney and generative organs.

The influence of phytoestrogens on different physiological and pathological processes: An overview

Functional foods have nutritional properties and organic functions, which are beneficial to health. Certain types of functional food components are so-called phytoestrogens, non-steroidal compounds derived from the metabolism of precursors contained in plants, which originate secondary metabotypes known to induce biological responses and by mimicry or modulating the action of endogenous estrogen. These molecules are involved in several physiological and pathological processes related to reproduction, bone remodeling, skin, cardiovascular, nervous, immune systems, and metabolism. This review aimed to present an overview of phytoestrogens regarding their chemical structure, actions, and effects in the organism given several pathologies. Several studies have demonstrated beneficial phytoestrogen actions, such as lipid profile improvement, cognitive function, menopause, oxidative stress, among others. Phytoestrogens effects are not completely elucidated, being necessary future research to understand the exact action mechanisms, whether they are via estrogen receptor or whether other hidden mechanisms produce these effects. Thus, this review makes a general approach to the phytoestrogen actions, beneficial effects, risk and limitations. However, the complexities of biological effects after ingestion of phytoestrogens and the differences in their metabolism and bioavailability indicate that interpretation of either risk or benefits needs to be made with caution.

Estrogen Receptor-Mediated Transcriptional Activities of Spent Coffee Grounds and Spent Coffee Grounds Compost, and Their Phenolic Acid Constituents

Spent coffee grounds (SCG) are the most abundant coffee byproduct and are generally discarded as waste. The horticultural use of SCG and SCG compost (SCGC) has become popular due to a growing interest in environmentally friendly measures for waste disposal. Estrogen-like endocrine disrupting chemicals in the soil can be absorbed by plants and subsequently by humans who consume these plants. The objectives of this study are to determine the phytochemical profiles of extracts of SCG and SCGC and to evaluate the estrogen-like activities of SCG, SCGC, and the major coffee phenolic acids, specifically, 5-O-caffeoylquinic acid (CQA), caffeic acid, and ferulic acid. Their inductive effects on estrogen receptor (ER)-mediated gene transcription have been examined in cultured cell lines. CQA was the most abundant phenolic acid in SCG and SCGC and was further examined for its ER-mediated estrogen-like activity using various assays. This is the first study to report the estrogen-like signaling activities of coffee byproducts and their major constituents.

Effect and mechanism of psoralidin on promoting osteogenesis and inhibiting adipogenesis

BACKGROUND

Psoralidin (PL), a prenylated coumestrol, is isolated from Psoralea corylifolia L. (Fabaceae), which is frequently used for treatment of osteoporosis.

PURPOSE

This study was designed to investigate the dual effects and potential mechanism of PL on promoting osteogenesis and inhibiting adipogenesis.

METHODS

Bone marrow mesenchymal stem cells (BMSCs) were used to investigate the effect of PL on stimulating osteogenesis and inhibiting adipogenesis, while preosteoblast MC3T3-E1 cells and preadipocyte 3T3-L1 cells were employed to explore the potential mechanisms. Estradiol (E₂) and ICI 182,780 (ICI) were used as the specific agonist and antagonist of classical estrogen receptors (ER), respectively, to interfere with classical ER signaling. Meanwhile, G-1 and G-15 were introduced as the selective agonist and antagonist of G protein coupled receptor 30 (GRP30, a membrane ER) to further clarify if membrane ER involved in PL mediating osteogenesis and adipogenesis RESULTS: PL not only promoted mineralization, but also inhibited adipocytes formation of BMSCs. In terms of osteogenesis, PL enhanced calcium nodule formation, alkaline phosphatase activity and osteocalcin levels in MC3T3-E1 cells. As for adipogenesis, PL decreased adipocyte formation in 3T3-L1 cells through down-regulating several mRNA expressions and protein synthesis of adipogenesis related factors. ICI completely blocked the effect of PL in promoting osteogenesis, but only partially suppressed its effect in inhibition of adipogenesis, while G-15 partially suppressed the effect of PL on promoting mineralization and inhibiting oil drop formation. Furthermore, during suppression of adipocyte differentiation, PL regulated protein kinase B / glycogen synthase kinase 3β / β-catenin signaling pathway.

CONCLUSION

PL promoted osteogenesis via mediating classical ER pathway, and inhibited adipocytes formation by regulating combined classical and membrane ER pathways. PL might be a potential candidate for the treatment of postmenopausal osteoporosis by modulating the competitive relationship between osteogenesis and adipogenesis of bone marrow mesenchymal stem cells.

Ionic Liquid-Based Ultrasonic-Assisted Extraction to Analyze Seven Compounds in Psoralea Fructus Coupled with HPLC

Psoralea Fructus is widely used in traditional Chinese medicine (TCM), and the content of psoralen, isopsoralen, neobavaisoflavone, bavachin, psoralidin, isobavachalcone, and bavachinin A is the main quality control index of Psoralea Fructus because of its clinical effects. Thus, a fast and environmentally-benign extraction method of seven compounds in Psoralea Fructus is necessary. In this work, an ionic liquid-based ultrasonic-assisted method (ILUAE) for the extraction of seven compounds from Psoralea Fructus was proposed. Several ILs of different types and parameters, including the concentration of ILs, concentration of ethanol (EtOH), solid–liquid ratio, particle size, ultrasonic time, centrifugal speed, and ultrasonic power, were optimized by the Placket–Burman (PB) design and Box–Behnken response surface analysis. Under this optimal condition, the total extraction yield of the seven compounds in Psoralea Fructus was 18.90 mg/g, and significantly greater than the conventional 75% EtOH solvent extraction.

Genus Psoralea: A review of the traditional and modern uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Psoralea (Fabaceae) harbours 105 accepted species that are extensively used by local peoples and medicinal practitioners of China, India, and other countries for treatment of tooth decay, psoriasis, leucoderma, leprosy, kidney problems, tuberculosis, indigestion, constipation and impotence. Presently, pharmacological research reports are available on only few species namely Bituminaria bituminosa (Syn: P. bituminosa), P. canescens, P. corylifolia, P. esculenta, P. plicata and P. glandulosa which are valued for their chemical constituents and traditional uses.

AIM OF THE REVIEW

This review article provides explicit information on traditional uses, phytochemistry, and pharmacological activities of selected Psoralea species. The possible trends and perspectives for future research on these plants are also discussed.

MATERIALS AND METHODS

An extensive and systematic review of the extant literature was carried out, and the data under various sections were identified using a computerized bibliographic search via the PubMed, Web of Science and Google Scholar, CAB Abstracts, MEDLINE, EMBASE, INMEDPLAN, NATTS as well as several websites.

KEY FINDINGS

A total of 291 bioactive compounds from 06 species of genus Psoralea have been isolated and characterized. However, P. bituminosa alone possess nearly 150 compounds. These bioactive compounds belong to different chemical classes, including flavonoids, coumarins, furanocoumarins, chalcones, quinines, terpenoids and some others due to which these species exhibit significant anti-oxidant, anti-bacterial, anti-fungal, anti-viral, anti-helmintic, anti-diabetic, diuretic, hepatoprotective, anti-cancer and anti-tumor activities. P. corylifolia L. (Babchi), a Chinese traditional medicinal plant has been used in traditional medicine for many decades for its healing properties against numerous skin diseases such as leprosy, psoriasis and leucoderma.

CONCLUSIONS

The in vitro studies and in vivo models have provided a simple bio-scientific justification for various ethnopharmacological uses of Psoralea species. From the toxicological perspective, the root, leaf, and seed extracts and their preparations have been proven to be safe when consumed in the recommended doses. But, meticulous studies on the pharmaceutical standardization, mode of action of the active constituents, and sustainable conservation of Psoralea species are needed, to meet the growing demands of the pharmaceutical industries, and to fully exploit their preventive and therapeutic potentials.

Characterization of Soybean Germinated Embryo Extract as an Estrogen Receptor Subtype-Selective and Tissue-Specific Modulator

Phytoestrogens possess beneficial effects in the management of menopausal symptoms with few side effects. Soybeans are major natural sources of isoflavones, with high estrogen receptor (ER)-β selectivity. The objective of this study therefore was to develop a solvent-mediated extraction method for soybean germinated embryos (SGEs) and to investigate the biological activities of the extract. Ethanolic extraction yielded the SGE extract (SGEE), which had a unique composition of biologically active aglycones and soyasaponins. SGEE showed a proliferative effect in MCF7 cells and ERβ-selective transcriptional activities in human embryonic kidney cells. In addition, oral administration of SGEE to ovariectomized rats resulted in the induction of ERβ and estrogen-responsive genes in the uterus and a decrease in tail skin temperature and uterus weight. Our data suggest that germination and ethanolic extraction are effective measures for producing isoflavone-rich food supplements, which may be useful as alternative menopausal hormone therapy.

Natural Estrogen Receptor Modulators and Their Heterologous Biosynthesis

Estrogen receptors (ERs) are transcription factors highly involved in physiological development and metabolism in the human body. They also play important roles in the treatment of cancer and metabolic diseases. Chemicals that interact with ERs can be used to treat diseases and maintain health. Phytoestrogens are natural chemicals that have been documented to possess significant ER modulatory activities. However, since phytoestrogens usually exist at low quantities in nature, heterologous biosynthesis techniques have quickly developed in recent years in order meet the demands for needed therapeutic amounts. In this review, the performance of phytoestrogens as ER modulators is described along with recent advances in biosynthesis techniques.

General survey of Fructus Psoraleae from the different origins and chemical identification of the roasted from raw Fructus Psoraleae

Fructus Psoraleae, a traditional Chinese medicine, is widely used for preventing and treating various diseases such as vitiligo, osteoporosis and psoriasis. Coumarin, such as psoralenoside, isopsoralenoside, psoralen and isopsoralen, are important compounds in Fructus Psoraleae. In our study, ultra performance liquid chromatography coupled with diode array detector was employed for an excellent method validation for simultaneous quantification of psoralenoside, isopsoralenoside, psoralen and isopsoralen, which was further applied in performing general survey of Fructus Psoraleae from the different origins and chemical identification of the roasted from raw Fructus Psoraleae in the light of illuminating the transformed rule of psoralenoside and isopsoralenoside. There is a reciprocal relationship between (iso)psoralenoside and (iso)psoralen, and the total content remains balance in Fructus Psoraleae from the different origins. In addition, we found that (iso)psoralenoside in the powder of the raw Fructus Psoraleae could be easily transformed into (iso)psoralen in methanol aqueous solution, especially above 50% water, rather than the roasted one. Thus, we proposed a hypothesis that transformation between (iso)psoralenoside and (iso)psoralen was hindered by inactivation of β-glucosidase in the process of roasting Fructus Psoraleae, which was further verified by observing transformation of (iso)psoralenoside under the different conditions, such as temperature, pH and β-glucosidase. Therefore, we developed a feasible method to distinguish the roasted from raw Fructus Psoraleae by observing conversion from (iso)psoralenoside to (iso)psoralen in 50% methanol aqueous solution. In summary, these results pave the way for elevating quality standard for Fructus Psoraleae and distinguishing the salt-processed from raw Fructus Psoraleae.

Psoralea corylifolia L: Ethnobotanical, biological, and chemical aspects: A review

Psoralea corylifolia L. (Leguminosae) is a well-known traditional medicinal plant used from ancient times for treatment of various ailments. It is widely distributed and an important part of therapeutics in Ayurveda and in Chinese medicines. The aim of this review is to present comprehensive and most up to date report on its ethnobotanical, ethnopharmacological, clinical, phytochemical, and side effects. Studies on the ethnobotanical, ethnopharmacological, clinical, phytochemical, and side effects of P. corylifolia were published until year 2017 and were searched using various scientific databases. The scientific literature searched revealed that these plant species has been extensively investigated in vivo and in vitro for various biological and phytochemical studies. It has cardiotonic, vasodilator, pigmentor, antitumor, antibacterial, cytotoxic, and anti-helminthic properties and locally used for alopecia, inflammation, leukoderma, leprosy, psoriasis, and eczema. So far, about a hundred bioactive compounds have been isolated from seeds and fruits, and most important compounds identified belongs to coumarins, flavonoids, and meroterpenes groups. This review article summarized the most updated scientific literature on bioactive phytochemical and biological activities of P. corylifolia. This article will be a useful addition to providing information for future research, and more standard clinical trials are needed for the plant to be used as therapeutic agent.

The potential health effects of dietary phytoestrogens

Phytoestrogens are plant-derived dietary compounds with structural similarity to 17-β-oestradiol (E2), the primary female sex hormone. This structural similarity to E2 enables phytoestrogens to cause (anti)oestrogenic effects by binding to the oestrogen receptors. The aim of the present review is to present a state-of-the-art overview of the potential health effects of dietary phytoestrogens. Various beneficial health effects have been ascribed to phytoestrogens, such as a lowered risk of menopausal symptoms like hot flushes and osteoporosis, lowered risks of cardiovascular disease, obesity, metabolic syndrome and type 2 diabetes, brain function disorders, breast cancer, prostate cancer, bowel cancer and other cancers. In contrast to these beneficial health claims, the (anti)oestrogenic properties of phytoestrogens have also raised concerns since they might act as endocrine disruptors, indicating a potential to cause adverse health effects. The literature overview presented in this paper illustrates that several potential health benefits of phytoestrogens have been reported but that, given the data on potential adverse health effects, the current evidence on these beneficial health effects is not so obvious that they clearly outweigh the possible health risks. Furthermore, the data currently available are not sufficient to support a more refined (semi) quantitative risk-benefit analysis. This implies that a definite conclusion on possible beneficial health effects of phytoestrogens cannot be made.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

The Chemical Constituents and Bioactivities of Psoralea corylifolia Linn.: A Review

Psoralea corylifolia Linn. (P. corylifolia) is an important medicinal plant with thousands of years of clinical application. It has been widely used in many traditional Chinese medicine formulas for the treatment of various diseases such as leucoderma and other skin diseases, cardiovascular diseases, nephritis, osteoporosis, and cancer. Phytochemical studies indicated that coumarins, flavonoids, and meroterpenes are the main components of P. corylifolia, and most of these components are present in the seeds or fruits. The extracts and active components of P. corylifolia demonstrated multiple biological activities, including estrogenic, antitumor, anti-oxidant, antimicrobial, antidepressant, anti-inflammatory, osteoblastic, and hepatoprotective activities. This paper systematically summarized literatures on the chemical constituents and biological activities of P. corylifolia, which provided useful information for the further research and development toward this potent medicinal plant.

Phytochemical and Pharmacological Studies on the Genus Psoralea: A Mini Review

The genus Psoralea, which belongs to the family Fabaceae, comprises ca. 130 species distributed all over the world, and some of the plants are used as folk medicine to treat various diseases. Psoralea corylifolia is a typical example, whose seeds have been widely used in many traditional Chinese medicine formulas for the treatment of various diseases such as leucoderma and other skin diseases, cardiovascular diseases, nephritis, osteoporosis, and cancer. So, the chemical and pharmacological studies on this genus were performed in the past decades. Here, we give a mini review on this genus about its phytochemical and pharmacological studies from 1910 to 2015.

Quantitative Analysis of Psoralea corylifolia Linne and its Neuroprotective and Anti-Neuroinflammatory Effects in HT22 Hippocampal Cells and BV-2 Microglia

The seeds of Psoralea corylifolia L. (P. corylifolia), also known as “Bo-Gol-Zhee” in Korea, are used in a traditional herbal medicine for treating various skin diseases. In the present study, we performed quantitative analyses of the seven standard components of P. corylifolia: psoralen, angelicin, neobavaisoflavone, psoralidin, isobavachalcone, bavachinin, and bakuchiol, using high-performance liquid chromatography. We also investigated the neuroprotective and anti-neuroinflammation effects of P. corylifolia and its standard components in the hippocampal cell line HT22 and microglia cell line BV-2. A 70% ethanol extract of P. corylifolia was prepared and the seven standard components were separated using C-18 analytical columns by gradient solvents with acetonitrile and water, and ultraviolet detection at 215, 225 and 275 nm. The analytical method showed high linearity, with a correlation coefficient of ≥0.9999. The amounts of the standard components ranged from 0.74 to 11.71 mg/g. Among the components, bakuchiol (11.71 mg/g) was the most potent phytochemical component of P. corylifolia. Furthermore, we analyzed the inhibitory effects of the components from P. corylifolia to determine the bioactive compound needed to regulate neuronal cell changes. Angelicin, isobavachalcone, and bakuchiol suppressed lipopolysaccharide (LPS)-stimulated nitric oxide production in LPS-treated BV-2 microglia more significantly than did the other components. In HT22 hippocampal cells, neobavaisoflavone and bakuchiol had more potent inhibitory activity against hydrogen peroxide-induced cell death. Taken together of the quantification and efficacy analyses, bakuchiol appeared to be the most potent bioactive phytochemical component of P. corylifolia for the potential treatment of neurodegenerative diseases.

Psoralidin induced reactive oxygen species (ROS)-dependent DNA damage and protective autophagy mediated by NOX4 in breast cancer cells

BACKGROUND

Psoralidin (PSO), a natural phenolic coumarin, was reported to have anti-cancer activities. PSO induced reactive oxygen species (ROS) generation in cancer cells. The role of ROS in its anti-cancer effect remains unclear.

PURPOSE

This study was designed to investigate the potential roles of ROS in PSO-induced anti-cancer effect in MCF-7 breast cancer cells.

METHODS

Effect of PSO on cancer cell proliferation was determined by MTT assay. Comet assay was used to determine DNA damage. Protein expression was detected by Western blotting. Autophagic vacuoles were detected by monodansylcadaverine (MDC) staining. ROS generation was measured by fluorescent probe. NOX4 localization was determined by immunofluorescence staining.

RESULTS

PSO treatment caused proliferation inhibition in time- and dose- dependent manners, which was partially reversed by N-acetyl cysteine (NAC) and diphenyleneiodonium (DPI). PSO induced DNA damage and increased protein expression of γ-H2AX, phosphorylation of ATM, ATR, Chk1, and Chk2. PSO induced autophagy as evidenced by the accumulation of autophagic vacuoles and alterations of autophagic protein expression. PSO-induced cell death was enhanced by autophagy inhibitor chloroquine (CQ). Furthermore, PSO treatment induced ROS formation, which was reversed by NAC or DPI pretreatment. The expression of NOX4 was significantly enhanced by PSO. Both NAC and DPI could reverse PSO-induced DNA damage and autophagic responses. In addition, silencing NOX4 by siRNA inhibited PSO-induced ROS generation, DNA damage, and autophagy.

CONCLUSIONS

Taken together, these results showed that PSO induced DNA damage and protective autophagy mediated by ROS generation in a NOX4-dependent manner in MCF-7 cells.

Danshen enhanced the estrogenic effects of Qing E formula in ovariectomized rats

BACKGROUND

Menopause is characterized by a decrease in life quality due to the appearance of uncomfortable symptoms. Nowadays, Understanding menopause-associated pathophysiology and developing new strategies to improve the treatment of menopausal-associated symptoms is an important issue. Our study was to evaluate the synergistic effects of Danshen (salvia miltiorrhiza bunge) and the phytoestrogenic effects of 3 modified Qing E formulas, to explore a better formula for menopausal disorders.

METHODS

100 rats were randomized into 5 groups: Sham (Sham operation group), OVX (model group of ovariectomized rat), BDL (group with low concentration of Qing E Formula), BDH (group with high concentration of Qing E Formula) and BDD (group with high concentration of Qing E Formula Plus Danshen), receiving vehicle and extract of different modified Qing E formula respectively. The food intake, body weight, uterus weight, blood levels of triglycerides (TG), total cholesterol (TC) and cholesterol fractions were assessed. The mammary glands and uterus were morphologically analyzed. The bone density of tibias were measured by peripheral quantitative computed tomography (pQCT). Additionally, luciferase induction assays were performed in Hela cells with the mixtures derived from Qing E formula plus Danshen (BDD).

RESULTS

Qing E formula plus Danshen significantly increased the uterus wet weight, enhanced the thickness of uterine wall, endometrial epithelium and glandular epithelium, improved trabecular bone and total density evidently, reduced the levels of low density lipoprotein cholesterol (LDL-C) and TG, possessed notable estrogen receptor beta (ERβ) and estrogen receptor alpha (ERα) agonist activity.

CONCLUSION

Qing E formula plus Danshen exerted more evident estrogen-like effects, thus it has a potential therapeutic use to treat menopausal disorders.

Synthesis of Psoralidin derivatives and their anticancer activity: First synthesis of Lespeflorin I1

Synthetic scheme for the preparation of a number of different derivatives of anticancer natural product Psoralidin is described. A convergent synthetic approach is followed using simple starting materials like substituted phenyl acetic esters and benzoic acids. The developed synthetic route leads us to complete the first synthesis of an analogous natural product Lespeflorin I₁, a mild melanin synthesis inhibitor. Preliminary bioactivity studies of the synthesized compounds are carried out against two commonly used prostate cancer cell lines. Results show that the bioactivity of the compounds can be manipulated by the simple modification of the functional groups.

Evaluation of the Biological Activity of Opuntia ficus indica as a Tissue- and Estrogen Receptor Subtype-Selective Modulator

Phytoestrogens are selective estrogen receptor modulators (SERMs) with potential for use in hormone replacement therapy (HRT) to relieve peri/postmenopausal symptoms. This study was aimed at elucidating the molecular mechanisms underlying the SERM properties of the extract of Korean-grown Opuntia ficus-indica (KOFI). The KOFI extract induced estrogen response element (ERE)-driven transcription in breast and endometrial cancer cell lines and the expression of endogenous estrogen-responsive genes in breast cancer cells. The flavonoid content of different KOFI preparations affected ERE-luciferase activities, implying that the flavonoid composition likely mediated the estrogenic activities in cells. Oral administration of KOFI decreased the weight gain and levels of both serum glucose and triglyceride in ovariectomized (OVX) rats. Finally, KOFI had an inhibitory effect on the 17β-estradiol-induced proliferation of the endometrial epithelium in OVX rats. Our data demonstrate that KOFI exhibited SERM activity with no uterotrophic side effects. Therefore, KOFI alone or in combination with other botanical supplements, vitamins, or minerals may be an effective and safe alternative active ingredient to HRTs, for the management of postmenopausal symptoms. Copyright © 2016 John Wiley & Sons, Ltd.

Estrogenic endocrine disruptors: Molecular mechanisms of action

A comprehensive summary of more than 450 estrogenic chemicals including estrogenic endocrine disruptors is provided here to understand the complex and profound impact of estrogen action. First, estrogenic chemicals are categorized by structure as well as their applications, usage and effects. Second, estrogenic signaling is examined by the molecular mechanism based on the receptors, signaling pathways, crosstalk/bypassing and autocrine/paracrine/homeostatic networks involved in the signaling. Third, evaluation of estrogen action is discussed by focusing on the technologies and protocols of the assays for assessing estrogenicity. Understanding the molecular mechanisms of estrogen action is important to assess the action of endocrine disruptors and will be used for risk management based on pathway-based toxicity testing.

Wedelolactone induces growth of breast cancer cells by stimulation of estrogen receptor signalling

Wedelolactone, a plant coumestan, was shown to act as anti-cancer agent for breast and prostate carcinomas in vitro and in vivo targeting multiple cellular proteins including androgen receptors, 5-lipoxygenase and topoisomerase IIα. It is cytotoxic to breast, prostate, pituitary and myeloma cancer cell lines in vitro at μM concentrations. In this study, however, a novel biological activity of nM dose of wedelolactone was demonstrated. Wedelolactone acts as agonist of estrogen receptors (ER) α and β as demonstrated by transactivation of estrogen response element (ERE) in cells transiently expressing either ERα or ERβ and by molecular docking of this coumestan into ligand binding pocket of both ERα and ERβ. In breast cancer cells, wedelolactone stimulates growth of estrogen receptor-positive cells, expression of estrogen-responsive genes and activates rapid non-genomic estrogen signalling. All these effects can be inhibited by pretreatment with pure ER antagonist ICI 182,780 and they are not observed in ER-negative breast cancer cells. We conclude that wedelolactone acts as phytoestrogen in breast cancer cells by stimulating ER genomic and non-genomic signalling pathways.

Psoralidin induces autophagy through ROS generation which inhibits the proliferation of human lung cancer A549 cells

Psoralidin (PSO), a natural furanocoumarin, is isolated from Psoralea corylifolia L. possessing anti-cancer properties. However, the mechanisms of its effects remain unclear. Herein, we investigated its anti-proliferative effect and potential approaches of action on human lung cancer A549 cells. Cell proliferation and death were measured by MTT and LDH assay respectively. Apoptosis was detected with Hoechst 33342 staining by fluorescence microscopy, Annexin V-FITC by flow cytometry and Western blot analysis for apoptosis-related proteins. The autophagy was evaluated using MDC staining, immunofluorescence assay and Western blot analyses for LC3-I and LC3-II. In addition, the reactive oxygen species (ROS) generation was measured by DCFH2-DA with flow cytometry. PSO dramatically decreased the cell viabilities in dose- and time-dependent manner. However, no significant change was observed between the control group and the PSO-treated groups in Hoechst 33342 and Annexin V-FITC staining. The expression of apoptosis-related proteins was not altered significantly either. While the MDC-fluorescence intensity and the expression ratio of LC3-II/LC3-I was remarkably increased after PSO treatment. Autophagy inhibitor 3-MA blocked the production of LC3-II and reduced the cytotoxicity in response to PSO. Furthermore, PSO increased intracellular ROS level which was correlated to the elevation of LC3-II. ROS scavenger N-acetyl cysteine pretreatment not only decreased the ROS level, reduced the expression of LC3-II but also reversed PSO induced cytotoxicity. PSO inhibited the proliferation of A549 cells through autophagy but not apoptosis, which was mediated by inducing ROS production.