β-Asarone inhibits gastric cancer cell proliferation

β-Asarone Inhibits Carboplatin Resistance in Retinoblastoma Cells Through the UCA1/miR-206/NRP1 Axis

Retinoblastoma (RB) is an aggressive form of eye cancer. β-Asarone is a bioactive component isolated from the medicinal plant Acorus tatarinowii Schott and has anticancer effects on various human cancers. However, reports regarding the role of β-Asarone in RB remain limited. Our study investigates the mechanisms of β-Asarone in regulating drug resistance in RB, providing a theoretical foundation for RB treatment. A carboplatin-resistant RB cell line was established and treated with β-Asarone, followed by overexpression of long non-coding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1). The half-maximal inhibitory concentration and cell apoptosis were determined. The levels of lncRNA UCA1/miR-206/neuropilin 1 (NRP1) were measured. The subcellular localization of lncRNA UCA1 was examined. The binding relationships between lncRNA UCA1 and microRNA (miR)-206, and between miR-206 and NRP1 were analyzed. NRP1 expression was analyzed by Western blot assay. We found that β-Asarone downregulated lncRNA UCA1 expression in carboplatin-resistant RB cells. Overexpression of lncRNA UCA1 reversed the inhibitory effect of β-Asarone on cell drug resistance and cell proliferation and reduced apoptosis. LncRNA UCA1 functioned as a sponge for miR-206, which suppressed NRP1 expression. Inhibition of miR-206 or overexpression of NRP1 could partially reverse the suppressive effect of β-Asarone on RB cell drug resistance. In conclusion, β-Asarone suppresses RB cell drug resistance through the lncRNA UCA1/miR-206/NRP1 axis.

A network pharmacological approach for the identification of potential therapeutic targets of Brahmi Nei - a complex traditional Siddha formulation

Brahmi Nei (BN), a traditional Indian polyherbal formulation has been described in classical texts for the treatment of anxiety and depression, as well as to fortify the immune system. The individual herbs of BN have been used for treatment of wide range of disorders including cognition, inflammation, skin ailments and cancer etc., This diverse basket of therapeutic activity suggests that BN may possess therapeutic benefits to other disorders. So, the present study aims to identify the potential therapeutic targets of BN using a network pharmacological approach to comprehend the multi target action of its multiple phytoconstituents. We have employed Randić Index for the first time to calculate the contribution score of module segregated targets towards diseases. Our results suggests that BN targets could also be effective in other diseases such as lysosomal storage disorders, respiratory disorders etc., apart from neurological disorders. The key targets with highest topological measures of Targets-(Pathway)-Targets network were identified as potential therapeutic targets of BN. And the top hit target PTGS2, a gene encoding for cyclooxygenase-2 was further evaluated using molecular docking, molecular dynamic simulation and in vitro studies. Our findings open up new therapeutic facets for BN that can be explored systematically in future.

Acori Tatarinowii Rhizoma: A comprehensive review of its chemical composition, pharmacology, pharmacokinetics and toxicity

Acori Tatarinowii Rhizoma (ATR, Shi Chang Pu in Chinese), a natural product with multiple targets in various diseases. This review provides the comprehensive summary of the chemical composition, pharmacological effects, pharmacokinetics parameters and toxicity of ATR. The results indicated that ATR possesses a wide spectrum of chemical composition, including volatile oil, terpenoids, organic acids, flavonoids, amino acids, lignin, carbohydrates and so on. Accumulating evidence from various studies has shown that ATR exerts a wide range of pharmacological properties, including protecting nerve cells, alleviating learning and memory impairment, anti-ischemic, anti-myocardial ischemia, anti-arrhythmic, anti-tumor, anti-bacterial, and anti-oxidant activities. Currently, ATR is widely used in the central nervous system, cardiovascular system, gastrointestinal digestive system, respiratory system in China, and for the treatment of epilepsy, depression, amnesia, consciousness, anxiety, insomnia, aphasia, tinnitus, cancers, dementia, stroke, skin diseases, and other complex diseases. Pharmacokinetic studies indicated that β-asarone, α-asarone, cis-methylisoeugenol, and asarylaldehyde, the active components of ATR, were absorbed slowly after oral administration of ATR. Moreover, toxicity studies have suggested that ATR has no carcinogenic, teratogenic and mutagenic toxicity. Nevertheless, long term or high-dose toxicity testing in animals to explore the acute and chronic toxicity of acori Tatarinowii Rhizoma is still lacking. In view of good pharmacological activities, ATR is expected to be a potential drug candidate for the treatment of Alzheimer’s disease, depression, or ulcerative colitis. However, further studies are needed to elucidate its chemical composition, pharmacological effects, molecular mechanisms and targets, improve its oral bioavailability, and clarify its potential toxicity.

β-asarone attenuates the proliferation, migration and enhances apoptosis of retinoblastoma through Wnt/β-catenin signaling pathway

PURPOSE

β-asarone is the prime component of essential oil extracted from Acori graminei Rhizoma, which plays an inhibitory role in various tumors. Here, we aim to investigate the functions as well as the mechanism of β-asarone in retinoblastoma (RB).

METHODS

RB cell lines SO-Rb50 and HXO-Rb44 were treated with different doses of β-asarone. Then, CCK8 and BrdU experiments were adopted to examine the RB cell proliferation. Wound healing test and Transwell assay were employed to detect cell migration and invasion. RB cell apoptosis was tested by flow cytometry and Western blot. An RB cell xenograft model was constructed on nude mice for testing the role of β-asarone on RB cell growth in vivo. RT-PCR and Western blot were used to determine the effect of β-asarone on Wnt/β-catenin signaling pathway. Furthermore, the Wnt/β-catenin pathway inhibitor PNU-74654 and activator HLY78 were administered to RB cells for confirming the effects of β-asarone in Wnt/β-catenin pathway.

RESULTS

In vivo experiment showed that β-asarone attenuated SO-Rb50 cell growth in nude mice. Further research found that β-asarone significantly repressed Wnt/β-catenin canonical pathway activation.

CONCLUSION

Prior inhibition of Wnt/β-catenin pathway abolished the antitumor effects induced by β-asarone. β-asarone exerted antitumor effects in RB cells by inactivating the Wnt/β-catenin signaling pathway.

β-Asarone suppresses TGF-β/Smad signaling to reduce the invasive properties in esophageal squamous cancer cells

Esophageal cancer is one of the most common malignancies which induces cancer-related death. Cancer metastasis and recurrence are the main obstacle faced in esophageal cancer treatment. β-Asarone has been shown to act as an anti-cancer reagent in various cancer types. However, the anti-cancer activities of β-Asarone in esophageal cancer have not been shown. In the current study, we show that β-Asarone suppressed the proliferation of esophageal squamous cancer cells (ESCC) in both dose- and time-dependent manners. Moreover, β-Asarone treatment increases activated caspase 3, caspase 9, and cleaved poly ADP-ribose polymerase, and induces apoptosis in ESCC. Additionally, β-Asarone also suppresses epithelial-mesenchymal transition (EMT) and the invasive and migratory abilities in ESCC. Interestingly, β-Asarone suppresses TGF-β/Smad signaling by inhibition of TGF-β-induced phosphorylation of Smad2 and Smad3. Importantly, we show that inhibition of TGF-β/Smad signaling activation is critical for β-Asarone-suppressed EMT. Our data revealed a novel role of β-Asarone which targets invasive properties by inhibiting TGF-β/Smad signaling activation in ESCC. Our study suggests the potential application of β-Asarone to reduce cancer metastasis and recurrence in esophageal cancer treatment.

Food-Borne Chemical Carcinogens and the Evidence for Human Cancer Risk

Commonly consumed foods and beverages can contain chemicals with reported carcinogenic activity in rodent models. Moreover, exposures to some of these substances have been associated with increased cancer risks in humans. Food-borne carcinogens span a range of chemical classes and can arise from natural or anthropogenic sources, as well as form endogenously. Important considerations include the mechanism(s) of action (MoA), their relevance to human biology, and the level of exposure in diet. The MoAs of carcinogens have been classified as either DNA-reactive (genotoxic), involving covalent reaction with nuclear DNA, or epigenetic, involving molecular and cellular effects other than DNA reactivity. Carcinogens are generally present in food at low levels, resulting in low daily intakes, although there are some exceptions. Carcinogens of the DNA-reactive type produce effects at lower dosages than epigenetic carcinogens. Several food-related DNA-reactive carcinogens, including aflatoxins, aristolochic acid, benzene, benzo[a]pyrene and ethylene oxide, are recognized by the International Agency for Research on Cancer (IARC) as causes of human cancer. Of the epigenetic type, the only carcinogen considered to be associated with increased cancer in humans, although not from low-level food exposure, is dioxin (TCDD). Thus, DNA-reactive carcinogens in food represent a much greater risk than epigenetic carcinogens.

Chemical Structure and Immune Activation of a Glucan From Rhizoma Acori Tatarinowii

Rhizoma Acori Tatarinowii is a traditional Chinese herb used to treat depression and coronary heart disease. Studies on its active components mainly focus on small molecular compounds such as asarone and other essential oil components, while the large molecular active components such as polysaccharides are ignored. In this study, we aimed to study the chemical structure and immune activation of polysaccharides from Rhizoma Acori Tatarinowii. In this study, a polysaccharide (RATAPW) was isolated and purified by DEAE-52 cellulose and Sephadex G-100 column chromatography from alkali extraction polysaccharide of Rhizoma Acori Tatarinowii. The average molecular weight of RATAPW was 2.51 × 10⁴ Da, and the total carbohydrate contents of RATAPW were 98.23 ± 0.29%. The monosaccharide composition, methylation, and nuclear magnetic resonance (NMR) analysis results displayed that the polysaccharide was α-1,4-glucan with short α-1,6 branches. Immunofluorescence assay and inhibitor neutralization assay indicated that RATAPW could promote the TNF-α production of RAW264.7 macrophage through the nuclear factor kappa B (NF-κB) molecular signaling pathway. Treatment with 200 μg/ml of RATAPW enhanced a 38.77% rise in the proliferation rate of spleen lymphocytes. RATAPW also enhances ConA-induced T cells and lipopolysaccharide (LPS)-induced B cell proliferation in a dose-dependent effect. Our study lays a foundation for the discovery of natural polysaccharide immune modulators or functional food from Rhizoma Acori Tatarinowii.

β-asarone suppresses HCT116 colon cancer cell proliferation and liver metastasis in part by activating the innate immune system

Studies have revealed that β-asarone exerts a powerful inhibitory effect on the proliferation of human cancer cells. The authors' previous study demonstrated that β-asarone could induce LoVo colon cancer cell apoptosis in vitro and in vivo, indicating its anticancer properties. The present study aimed to determine the antineoplastic effect of β-asarone in HCT116 colon cancer cells. An in vitro proliferation assay using a real time cell analyzer demonstrated that β-asarone effectively decreased HCT116 cell proliferation in a dose-dependent manner. Bioinformatics analysis revealed that differentially expressed genes following β-asarone inhibition were involved in the 'cell cycle', 'cell division', 'cell proliferation' and 'apoptosis'. Subsequently, a xenograft assay evidenced the inhibitory effect of β-asarone on the growth of HCT116 tumors in vivo. Further detection of immune-associated cytokines and cells suggested that β-asarone might be involved in the antitumor immune response by stimulating granulocyte-colony stimulating factor and increasing the number of macrophage cells in the spleen. Additionally, a murine model of splenic-transplantation verified the strong suppressive role of β-asarone in colon cancer liver metastasis in vivo. Taken together, the results of the current study revealed that β-asarone decreased HCT116 colon cancer cell proliferation and liver metastasis potentially by activating the innate immune system, supporting the multi-system regulation theory and providing a basis for further mechanistic studies on colon cancer.

β-Asarone Increases Chemosensitivity by Inhibiting Tumor Glycolysis in Gastric Cancer

β-asarone is the main active ingredient of the Chinese herb Rhizoma Acori Tatarinowii, which exhibits a wide range of biological activities. It was confirmed to be an efficient cytotoxic agent against gastroenteric cancer cells. However, the exact mechanism of β-asarone in gastric cancer (GC) remains to be elucidated. The present study showed the inhibitory effect of β-asarone on three types of different differentiation stage GC cell lines (MGC803, SGC7901, and MKN74) in a dose-dependent manner. Meanwhile, the synergistic sensitivity of β-asarone and cisplatin was confirmed by using the median-effect principle. Flow cytometry assay revealed that under both normoxia and CoCl₂-induced hypoxia conditions, β-asarone can induce apoptosis of GC cells, which can block GC cells in the cell cycle G2/M phase, showing obvious subdiploid peak. Moreover, the activity of lactic dehydrogenase (LDH), an enzyme that plays an important role in the final step of tumor glycolysis, was significantly decreased in GC cells following treatment with β-asarone. Mechanistically, β-asarone can reduce pyruvate dehydrogenase kinase (PDK) 1, phospho(p)-PDK1, PDK4, hypoxia-inducible factor 1-α (HIF1α), c-myc, STAT5, and p-STAT5 expression, which revealed how β-asarone affects tumor glycolysis. In conclusion, the present study provided evidence in support of the hypothesis that the increase of chemotherapy sensitization by β-asarone is associated with the inhibition of tumor glycolysis.

β-asarone relieves chronic unpredictable mild stress induced depression by regulating the extracellular signal-regulated kinase signaling pathway

The present study aimed to investigate the effect of β-asarone treatment in a rat model of depression induced by chronic unpredictable mild stress (CUMS) and to further explore the underlying molecular mechanisms. A rat model of depression was established by subjecting rat to CUMS and treated with various concentrations of β-asarone (12.5, 25 and 50 mg/kg/day) and fluoxetine (20 mg/kg/day). Next, behavioral tests, including an open field, sucrose preference and forced swimming tests, were performed. In addition, the apoptosis of hippocampal neuronal cells was determined by flow cytometry, gene expression levels were detected by reverse transcription-quantitative polymerase chain reaction and protein levels were determined by western blot assay. The results revealed that β-asarone significantly mitigated CUMS-induced depression-like behavior, evidenced by the increased sucrose intake, crossing and rearing numbers, and decreased immobility time in the forced swimming test. Furthermore, β-asarone significantly decreased the apoptosis rate of hippocampal neuronal cells in rats subjected to CUMS. β-asarone was also found to enhance CREB, BDNF, Trk-B and Bcl-2 levels, and reduce Bad level in the hippocampus of CUMS-treated rats. In addition, the activation of extracellular signal-regulated kinase pathway inhibited by CUMS was promoted by β-asarone treatment. In conclusion, the present study findings indicated the antidepressant-like effects of β-asarone on CUMS-induced depression in rats.

Cytotoxic effects of β-asarone on Sf9 insect cells

β-Asarone is the predominant component of the essential oil of rhizomes of Acorus calamus Linn ( Sweet flag). Although rhizome extracts from this plant have long been used for insect pest control, their cytotoxic effects on insect cells are not well understood. In this study, we evaluated the potency of β-asarone as a natural insecticide by using a Spodoptera frugiperda cell line (Sf9). To assess the cytotoxic effects of β-asarone on Sf9 cells, we observed morphologic changes in treated cells and performed a cell proliferation assay and a DNA fragmentation assay. After 24 and 48 h of treatment with β-asarone, the proliferation of the Sf9 cells was inhibited in a dose-dependent manner, with IC₅₀ values of 0.558 mg/ml at 24 h and 0.253 mg/ml at 48 h. Morphologic changes in β-asarone-treated cells were typical of apoptosis and included loss of adhesion, cell shrinkage, and small apoptotic bodies. The DNA laddering present in β-asarone-treated SF9 cells and annexin V assay confirmed that this compound can induce apoptosis in insect cells. Together, these findings suggest that apoptosis induction may be one mechanism through which β-asarone inhibits the proliferation of insect cells and thus exerts insecticidal effects.

β-Asarone increases doxorubicin sensitivity by suppressing NF-κB signaling and abolishes doxorubicin-induced enrichment of stem-like population by destabilizing Bmi1

Background

Lymphoma is one of the most common hematologic malignancy. Drug resistance is the main obstacle faced in lymphoma treatment. Cancer stem cells are considered as the source of tumor recurrence, metastasis and drug resistance. The β-Asarone, a low-toxicity compound from the traditional medical herb Acorus calamus, has been shown to act as an anti-cancer reagent in various cancer types. However, the anti-cancer activities of β-Asarone in lymphoma have not been shown.

Methods

Cell counting assay was used to evaluate Raji cell proliferation. CCK8 assay was used to evaluate the cell viability. Annexin-V/PI staining and flow cytometry analysis were used to evaluate apoptosis. ALDEFLUOR assay was used to evaluate the stem-like population. Luciferase reporter assay was used to examine the activation of NF-κB signaling. Western blot and polymerase chain reaction (PCR) were used to determine the expression of interested genes.

Results

We showed that β-Asarone inhibited proliferation and induced apoptosis in Raji lymphoma cells in a dose-dependent manner. Additionally, β-Asarone functioned as a sensitizer of doxorubicin and resulted in synergistic effects on inhibition of proliferation and induction of apoptosis when combined with doxorubicin treatment. Interestingly, we found that β-Asarone also reduced the stem-like population of Raji lymphoma cells in a dose-dependent manner, and suppressed the expression of c-Myc and Bmi1. Importantly, β-Asarone abolished doxorubicin-induced enrichment of the stem-like population. In the mechanism study, we revealed that β-Asarone suppressed not only basal NF-κB activity but also Tumor necrosis factor α (TNF-α) induced NF-κB activity. Moreover, blocking NF-κB signaling inactivation was critical for β-Asarone induced apoptosis and inhibition of proliferation, but not for the effect on β-Asarone reduced stem-like population. In fact, β-Asarone suppressed stem-like population by destabilizing Bmi1 via a proteasome-mediated mechanism.

Conclusions

Our data suggested the application of β-Asarone to lower the toxic effect of doxorubicin and increase the sensitivity of doxorubicin in clinical treatment. More importantly, our data revealed a novel role of β-Asarone which could be used to eliminate stem-like population in lymphoma, implying that β-Asarone might reduce relapse and drug resistance.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0873-3) contains supplementary material, which is available to authorized users.

Experimental evidence for use of Acorus calamus (asarone) for cancer chemoprevention

Cancer is one of the major non-communicable diseases posing substantial challenges in both developing and developed countries. The options available for treatment of different cancer are associated with various limitations, including severe toxicity, drug resistance, poor outcomes and a high risk of relapse. Hence, an increased attention and necessity for screening of various phytochemicals from natural sources for superior and safer alternative has been ongoing for several decades. In recent years, phytochemicals like galantamine, erwinaze, rivastigmine, resveratrol from natural sources have been found to be important therapeutic targets for the treatment of various diseases including cancer, neurodegeneration, diabetes, and cardiovascular effects. Acorus calamus (Sweet flag), and/or its bioactive phytochemical alpha (α)-and beta (β)-asarone, is a well-known drug in the traditional system of medicine which possesses anti-tumor and chemo-preventive activities as evident from numerous pre-clinical studies both in-vitro and in-vivo. In this article, we critically review the current available scientific evidences of A. calamus and/or asarone for cancer chemoprevention based on preclinical in-vitro and in-vivo models. In addition, we also have compiled and discussed the molecular targets of mechanism(s) involved in the anti-cancer activity of A. calamus/asarone. Still, extensive in-vivo studies are necessary using various animal models to understand the molecular mechanism behind the pharmacological activity of the bioactive phytochemicals derived from A. calamus. It is strongly believed that the comprehensive evidence presented in this article could deliver a possible source for researchers to conduct future studies pertaining to A. calamus and/or its bioactive phytochemicals asarone for cancer chemoprevention.

Effects of siRNA-mediated silencing of Bmi-1 gene expression on proliferation of gastric cancer cells

This study was designed to investigate the effects of siRNA-mediated silencing of Bmi-1 gene expression on proliferation of AGS gastric cancer cell. siRNA Bmi-1 was transfected into human AGS gastric cancer cells by liposome (as siRNA Bmi-1 group) with negative control (as control group); the expressions of Bmi-1 and apoptosis-related genes like P21, Bax, and Bcl-2 in AGS cells were determined by Western blot method; the apoptosis of AGS cells was detected by flow cytometry double staining and Hoechst staining; and cell cycle was measured by flow cytometry. Compared with the control group, the expression of Bmi-1 in the siRNA Bmi-1 group was significantly decreased ( P < 0.05), the apoptosis rate was increased ( P < 0.05), and cell cycles were arrested at G1 phase (P < 0.05); the expression level of P21 and Bax in cells was significantly up-regulated while that of Bcl-2 down-regulated ( P < 0.05). The down regulation of Bmi-1 can inhibit the proliferation of AGS gastric cancer cell and promote its apoptosis, which takes such effects mainly by up-regulating P21 as well as Bax and down-regulating Bcl-2.

β-Asarone suppresses Wnt/β-catenin signaling to reduce viability, inhibit migration/invasion/adhesion and induce mitochondria-related apoptosis in lung cancer cells

Lung cancer is the leading cause of cancer death worldwide. Chemotherapy is one of the most effective strategies for lung cancer treatment. However, the side effects of chemotherapy limit the application of chemotherapeutic agents. The β-Asarone, a low-toxicity natural compound from a traditional Chinese medicinal herb, has been demonstrated to display anticancer activities in multiple cancer types. However, the anticancer activities of β-Asarone in lung cancer have not been shown, and the underlying molecular mechanisms are still unclear. In the current study, we show that β-Asarone displays a dose-dependent inhibitory effect on the viability of lung cancer cells. Additionally, β-Asarone significantly suppresses the cell migration, invasion, and adhesion of lung cancer cells. Moreover, β-Asarone induces apoptosis associated with the activation of caspase-9 and caspase-3, the upregulation of XAF1, Puma, Bax (Ser184) and Bad (Ser112), the downregulation of XIAP, Bcl-2 and Survivin, the translocation of Bax, Bad, phospho-Bax (Ser184), phospho-Bad (Ser112) and cytochrome C and the reduction of the mitochondrial membrane potential. Mechanistically, our study shows that β-Asarone inhibits Wnt/β-catenin signaling. Rescuing the activation of Wnt/β-catenin signaling overcomes β-Asarone-induced anticancer effects. Taken together, our data provide the first evidence of the anticancer effects of β-Asarone in lung cancer, demonstrates that the inhibition of Wnt/β-catenin signaling could be critical for β-Asarone-induced anticancer effects. Our study thus suggests a potential application of β-Asarone as an anticancer agent in the clinical treatment of lung cancer.

β-Asarone Induces Apoptosis and Cell Cycle Arrest of Human Glioma U251 Cells via Suppression of HnRNP A2/B1-Mediated Pathway In Vitro and In Vivo

HnRNP A2/B1 has been found to be an oncogenic protein strongly related to the growth of human glioma cells. Herein, β-asarone, the main component in the volatile oil of Acori tatarinowii Rhizoma, inhibited the cell viability, proliferation, and colony formation ability of U251 cells. Moreover, β-asarone induced apoptosis and cell cycle arrest at the G1 phase. Notably, β-asarone suppressed the expression of hnRNP A2/B1 and hnRNPA2/B1 overexpression remarkably reversed β-asarone-mediated apoptosis and cell cycle arrest. Importantly, β-asarone promoted the alternative splicing of Bcl-x by enhancing the ratio of Bcl-xS/Bcl-xL. Meanwhile, hnRNPA2/B1 overexpression mitigated the promoting effect of β-asarone on the alternative splicing of Bcl-x. β-asarone also regulated the level of the key proteins involved in the death receptor pathway and mitochondrial apoptosis pathway. Additionally, β-asarone modulated the cell cycle-related proteins p21, p27, Cdc25A, cyclin D, cyclin E, and CDK2. Finally, β-asarone inhibited tumor growth and induced apoptosis in nude mice bearing U251 tumor xenografts. β-asarone also suppressed the hnRNP A2/B1 expression, enhanced the expression of cleaved-caspase 3 and p27 and the ratio of Bcl-xS/Bcl-xL, and reduced the expression of CDK2 in U251 xenografts. Together, β-asarone-induced apoptosis and cell cycle arrest of U251 cells may be related to the suppression of hnRNPA2/B1-mediated signaling pathway.

β-asarone inhibited cell growth and promoted autophagy via P53/Bcl-2/Bclin-1 and P53/AMPK/mTOR pathways in Human Glioma U251 cells

Glioma is the most common type of primary brain tumor and has an undesirable prognosis. Autophagy plays an important role in cancer therapy, but it is effect is still not definite. P53 is an important tumor suppressor gene and protein that is closely to autophagy. Our aim was to study the effect of β-asarone on inhibiting cell proliferation in human glioma U251 cells and to detect the effect of the inhibition on autophagy through the P53 signal pathway. For cell growth, the cells were divided into four groups: the model, β-asarone, temozolomide (TMZ), and co-administration groups. For cell autoghapy and the P53 pathway, the cells were divided into six groups: the model, β-asarone, 3MA, Rapa, Pifithrin-µ, and NSC groups. The counting Kit-8 assay and flow cytometry (FCM) were then used to measure the cell proliferation and cycle. Electron microscopy was used to observe autophagosome formation. Cell immunohistochemistry/-immunofluorescence, FCM and Western blot (WB) were used to examine the expression of Beclin-1 and P53. The levels of P53 and GAPDH mRNA were detected by RT-PCR. Using WB, we determined autophagy-related proteins Beclin-1, LC3-II/I, and P62 and those of the P53 pathway-related proteins P53, Bcl-2, mTOR, P-mTOR, AMPK, P-AMPK, and GAPDH. We got the results that β-asarone changed the cellular morphology, inhibited cell proliferation, and enhanced the expression of P53, LC3-II/I, Beclin-1, AMPK, and pAMPK while inhibiting the expression of P62, Bcl-2, mTOR, and pmTOR. All the data suggested that β-asarone could reduce the cell proliferation and promote autophagy possible via the P53 pathway in U251 cells.

Pharmacology and toxicology of α- and β-Asarone: A review of preclinical evidence

BACKGROUND

Asarone is one of the most researched phytochemicals and is mainly present in the Acorus species and Guatteria gaumeri Greenman. In preclinical studies, both α- and β-asarone have been reported to have numerous pharmacological activities and at the same time, many studies have also revealed the toxicity of α- and β-asarone.

PURPOSE

The purpose of this comprehensive review is to compile and analyze the information related to the pharmacokinetic, pharmacological, and toxicological studies reported on α- and β-asarone using preclinical in vitro and in vivo models. Besides, the molecular targets and mechanism(s) involved in the biological activities of α- and β-asarone were discussed.

METHODS

Databases including PubMed, ScienceDirect and Google scholar were searched and the literature from the year 1960 to January 2017 was retrieved using keywords such as α-asarone, β-asarone, pharmacokinetics, toxicology, pharmacological activities (e.g. depression, anxiety).

RESULTS

Based on the data obtained from the literature search, the pharmacokinetic studies of α- and β-asarone revealed that their oral bioavailability in rodents is poor with a short plasma half-life. Moreover, the metabolism of α- and β-asarone occurs mainly through cytochrome-P450 pathways. Besides, both α- and/or β-asarone possess a wide range of pharmacological activities such as antidepressant, antianxiety, anti-Alzheimer's, anti-Parkinson's, antiepileptic, anticancer, antihyperlipidemic, antithrombotic, anticholestatic and radioprotective activities through its interaction with multiple molecular targets. Importantly, the toxicological studies revealed that both α- and β-asarone can cause hepatomas and might possess mutagenicity, genotoxicity, and teratogenicity.

CONCLUSIONS

Taken together, further preclinical studies are required to confirm the pharmacological properties of α-asarone against depression, anxiety, Parkinson's disease, psychosis, drug dependence, pain, inflammation, cholestasis and thrombosis. Besides, the anticancer effect of β-asarone should be further studied in different types of cancers using in vivo models. Moreover, further dose-dependent in vivo studies are required to confirm the toxicity of α- and β-asarone. Overall, this extensive review provides a detailed information on the preclinical pharmacological and toxicological activities of α-and β-asarone and this could be very useful for researchers who wish to conduct further preclinical studies using α- and β-asarone.