In vivo effect of casticin on acute inflammation

Traditional use, phytochemistry and pharmacology of Viticis Fructus

Ethnopharmacological relevance

Viticis Fructus (called Manjingzi in China) is the dried ripe fruits of the plant species Vitex trifolia subsp. litoralis Steenis and Vitex trifolia L. in the family Lamiaceae. Viticis Fructus has been used as a traditional Chinese medicine for thousands of years to treat illness such as colds, headache, vertigo, anesthesia, and hyperkinesias. More chemical constituents and medicinal effects have been discovered in Viticis Fructus with the development of modern technology.The aim of the review: This review aims to analyze the research progress of Viticis Fructus from the aspects of botany, ethnopharmacology, phytochemistry, and pharmacological activity, as well as to provide an outlook on the research and use prospects of Viticis Fructus.

Material and methods

A comprehensive literature search using online databases such Science Direct, CNKI, Wiley online library, Spring Link, Web of Science, PubMed, Wanfang Data and SCI-Finder. In addition, information was obtained from local and foreign books on ethnobotany and ethnomedicine.

Results

The application of Viticis Fructus as a medicine can be traced back to around 480 AD. So far, more than 190 compounds have been isolated from Viticis Fructus, including flavonoids, sterols, cyclic enol ether terpenoids, and diterpenoids. Modern pharmacological studies have shown that the extracts of Viticis Fructus have various pharmacological effects, such as anti-allergic, antioxidant, anti-inflammatory, anti-cancer, and anti-bacterial effects.

Conclusion

As a widely used traditional medicine, Viticis Fructus is rich in chemical compositions and has an obvious biological activity. However, the application and pharmacological activity of Viticis Fructus have not been scientifically evaluated or convincing due to poor methodology, unclear results and lack of clinical data. Systematic and comprehensive research evaluations are needed to verify its pharmaceutical activity, clinical therapeutic efficacy and safety. As an important herbal medicine, it should be further explored to facilitate the development of new medicines and treatments for a variety of diseases.

miR-338-3p Plays a Significant Role in Casticin-Induced Suppression of Acute Myeloid Leukemia via Targeting PI3K/Akt Pathway

Objective

Casticin is generally used in traditional herbal medicine for its anti-inflammatory and anticarcinogenic pharmacological properties. Also, microRNAs are indispensable oncogenes or cancer suppressors being dysregulated in various diseases. In this study, we aimed to elucidate the mechanisms underlying effects of casticin on the progression of acute myeloid leukemia (AML).

Methods

CCK-8 and flow cytometry were utilized to measure the proliferation and apoptosis of AML cell lines, respectively, after treatment with different concentrations of casticin. The alteration of several microRNA expressions in response to casticin treatment was detected by performing qRT-PCR, and the activity of PI3K/Akt pathways was evaluated through immunoblotting. Afterwards, the potential target gene of miR-338-3p was investigated by dual-luciferase reporter assay. In order to evaluate the role of miR-338-3p in the casticin-induced cellular phenotype changes, AML cells were transfected with miR-338-3p mimics or inhibitor and then subjected to proliferation and apoptosis analysis. Finally, a mouse xenograft model system was employed to investigate the role of casticin in AML progression in vivo.

Results

Suppressed cellular proliferation and enhanced apoptosis were observed in HL-60 and THP-1 cells after exposure to casticin, accompanied by remarkable upregulation of the miR-338-3p expression as well as a decline in the phosphorylation of PI3K and Akt proteins. RUNX2 was identified as a direct target molecular of miR-338-3p, which might account for the findings that miR-338-3p knockdown enhanced the PI3K/Akt pathway activity, whereas the miR-338-3p overexpression inactivated this signaling pathway. In addition, the inhibition of the miR-338-3p expression attenuated severe cell apoptosis and suppressions of PI3K/Akt pathway induced by casticin. Furthermore, casticin treatment retarded tumor growth rate in mouse models, whilst elevating miR-338 expression and repressing the activity of PI3K/Akt pathway in vivo. However, miR-338-3p depletion could also abolish the phenotypic alterations caused by casticin treatment.

Conclusion

Casticin promotes AML cell apoptosis but inhibits AML cell proliferation in vitro and tumor growth in vivo by upregulating miR-338-3p, which targets RUNX2 and thereafter inactivates PI3K-Akt signaling pathway. Our results provide insights into the mechanisms underlying the action of casticin in the control of AML progression.

Casticin Inhibits In Vivo Growth of Xenograft Tumors of Human Oral Cancer SCC-4 Cells

BACKGROUND/AIM

Casticin, one of the active components of Vitex rotundifolia L., presents biological and pharmacological activities including inhibition of migration, invasion and induction of apoptosis in numerous human cancer cells in vitro. This study aimed to assess the effects of casticin on tumor growth in a human oral cancer SCC-4 cell xenograft mouse model in vivo.

MATERIALS AND METHODS

Twenty-four nude mice were injected subcutaneously with SCC-4 cells and when palpable tumors reached a volume of 100-120 mm³ the mice were randomly divided into three groups. The control (0.1% dimethyl sulfoxide), casticin (0.2 mg/kg), and casticin (0.4 mg/kg) groups were intraperitoneally injected every two days for 18 days. Tumor volume and body weights were measured every two days.

RESULTS

Casticin significantly decreased tumor volume and weight in SCC-4 cell xenograft mice but there was no statistically significant difference between the body weights of control mice and mice treated with 0.2 mg/kg or 0.4 mg/kg casticin. Therefore, the growth of SCC-4 cells in athymic nude mice can be inhibited by casticin in vivo.

CONCLUSION

These findings support further investigations in the potential use of casticin as an oral anti-cancer drug in the future.

Casticin-Induced Inhibition of Cell Growth and Survival Are Mediated through the Dual Modulation of Akt/mTOR Signaling Cascade

The Akt/mTOR signaling cascade is a critical pathway involved in various physiological and pathological conditions, including regulation of cell proliferation, survival, invasion, and angiogenesis. In the present study, we investigated the anti-neoplastic effects of casticin (CTC), identified from the plant Vitex rotundifolia L., alone and/or in combination with BEZ-235, a dual Akt/mTOR inhibitor in human tumor cells. We found that CTC exerted a significant dose-dependent cytotoxicity and reduced cell proliferation in a variety of human tumor cells. Also, CTC effectively blocked the phosphorylation levels of Akt (Ser473) and mTOR (Ser2448) proteins as well as induced substantial apoptosis. Additionally treatment with CTC and BEZ-235 in conjunction resulted in a greater apoptotic effect than caused by either agent alone thus implicating the anti-neoplastic effects of this novel combination. Overall, the findings suggest that CTC can interfere with Akt/mTOR signaling cascade involved in tumorigenesis and can be used together with pharmacological agents targeting Akt/mTOR pathway.

Casticin from Vitex species: a short review on its anticancer and anti-inflammatory properties

This short review provides an update of the anticancer and anti-inflammatory properties of casticin from Vitex species. Casticin is a polymethylflavone with three rings, an orthocatechol moiety, a double bond, two hydroxyl groups and four methoxyl groups. Casticin has been isolated from various tissues of plants in the Vitex genus: fruits and leaves of V. trifolia, aerial parts and seeds of V. agnus-castus and leaves of V. negundo. Studies have reported the antiproliferative and apoptotic activities of casticin from Vitex species. The compound is effective against many cancer cell lines via different molecular mechanisms. Studies have also affirmed the anti-inflammatory properties of casticin, with several molecular mechanisms identified. Other pharmacological properties include anti-asthmatic, tracheospasmolytic, analgesic, antihyperprolactinemia, immunomodulatory, opioidergic, oestrogenic, anti-angiogenic, antiglioma, lung injury protection, rheumatoid arthritis amelioration and liver fibrosis attenuation activities. Clinical trials and commercial use of the casticin-rich fruit extract of V. agnus-castus among women with premenstrual syndrome were briefly discussed.

Casticin inhibits the epithelial-mesenchymal transition in ovarian carcinoma via the hedgehog signaling pathway

Casticin inhibits migration, invasion and induced apoptosis in numerous cancer cells; however, the Hedgehog (Hh) signaling pathway is a key factor in the epithelial-mesenchymal transition (EMT). The present study aimed to assess whether casticin affects the expression of members of the Hh signaling pathway and EMT effectors in ovarian carcinoma. The ovarian cancer SKOV3 cell line was incubated in the presence of various concentrations of casticin or cyclopamine. Next, the expression levels of the main Hh signaling effector glioma-associated oncogene-1 (Gli-1) and EMT-associated factors [Twist-related protein 1 (Twist1), E-cadherin and N-cadherin] were determined by western blotting and reverse transcription-quantitative polymerase chain reaction. Cell proliferation and growth were assessed using MTT and soft agar assays; cell migration and invasion was evaluated using an in vitro migration assay and a transwell invasion assay, respectively. Compared with control group values, Gli-1, Twist1 and N-cadherin expression levels were reduced, whereas E-cadherin levels were increased in the casticin- and cyclopamine-treated groups. Incubation with casticin or cyclopamine resulted in markedly reduced SKOV3 cell viability, migration and invasion, in a dose-dependent manner. To the best of our knowledge, the findings of the present study indicated for first time that casticin may inhibit EMT via Hh signaling in vitro, reducing the migratory ability of ovarian cancer cells.

Casticin Induced Apoptosis in A375.S2 Human Melanoma Cells through the Inhibition of NF-[Formula: see text]B and Mitochondria-Dependent Pathways In Vitro and Inhibited Human Melanoma Xenografts in a Mouse Model In Vivo

Casticin, a polymethoxyflavone occurring in natural plants, has been shown to have anticancer activities. In the present study, we aims to investigate the anti-skin cancer activity of casticin on melanoma cells in vitro and the antitumor effect of casticin on human melanoma xenografts in nu/nu mice in vivo. A flow cytometric assay was performed to detect expression of viable cells, cell cycles, reactive oxygen species production, levels of [Formula: see text] and caspase activity. A Western blotting assay and confocal laser microscope examination were performed to detect expression of protein levels. In the in vitro studies, we found that casticin induced morphological cell changes and DNA condensation and damage, decreased the total viable cells, and induced G2/M phase arrest. Casticin promoted reactive oxygen species (ROS) production, decreased the level of [Formula: see text], and promoted caspase-3 activities in A375.S2 cells. The induced G2/M phase arrest indicated by the Western blotting assay showed that casticin promoted the expression of p53, p21 and CHK-1 proteins and inhibited the protein levels of Cdc25c, CDK-1, Cyclin A and B. The casticin-induced apoptosis indicated that casticin promoted pro-apoptotic proteins but inhibited anti-apoptotic proteins. These findings also were confirmed by the fact that casticin promoted the release of AIF and Endo G from mitochondria to cytosol. An electrophoretic mobility shift assay (EMSA) assay showed that casticin inhibited the NF-[Formula: see text]B binding DNA and that these effects were time-dependent. In the in vivo studies, results from immuno-deficient nu/nu mice bearing the A375.S2 tumor xenograft indicated that casticin significantly suppressed tumor growth based on tumor size and weight decreases. Early G2/M arrest and mitochondria-dependent signaling contributed to the apoptotic A375.S2 cell demise induced by casticin. In in vivo experiments, A375.S2 also efficaciously suppressed tumor volume in a xenotransplantation model. Therefore, casticin might be a potential therapeutic agent for the treatment of skin cancer in the future.

Casticin Inhibits A375.S2 Human Melanoma Cell Migration/Invasion through Downregulating NF-κB and Matrix Metalloproteinase-2 and -1

Casticin is one of the main components from Fructus Viticis, which is widely used as an anti-inflammatory agent. The mechanism of how casticin affects melanoma cell migration and invasion is still not well known. Here we studied the anti-metastasis effects of casticin on A375.S2 melanoma cells by using a non-lethal concentration. First; we used an adhesion assay to test the A375.S2 cells’ adhesion ability after treatment with casticin. We next investigated the cell migration ability after casticin treatment by using a wound healing assay to prove that the migration of A375.S2 cells can be inhibited by casticin and double checked the results using the transwell-migration assay. The suppressive effects on matrix metalloproteinase-2; and -9 (MMP-2; and -9) activities were examined by gelatin zymography. Furthermore, western blotting was used to investigate the protein level changes in A375.S2 cells. We found that p-EGFR; Ras and p-ERK1/2 are decreased by casticin, indicating that casticin can down-regulate the migration and invasion ability of A375.S2 cells via the p-EGFR/Ras/p-ERK pathway. The NF-κB p65 and p-ERK levels in nuclear proteins are also decreased by treatment with casticin. An EMSA assay also discovered that the NF-κB p65 and DNA interaction is decreased. NF-κB p65 protein level was examined by immunofluorescence staining and also decreased. Our findings suggest that casticin has anti-metastatic potential by decreasing the invasiveness of A375.S2 cells. We also found that casticin suppressed A375.S2 cell proliferation and cell adhesion ability, but did not affect cell death, as examined using cytometry and a collagen adhesion assay. Based on these observations, casticin could be used as an inhibitor of migration and invasion of human melanoma cells in the future.

Activation of the apoptosis signal-regulating kinase 1/c-Jun N-terminal kinase pathway is involved in the casticin-induced apoptosis of colon cancer cells

Casticin is one of the main components of the fruits of Vitex rotundifolia L. Studies have shown that casticin inhibits the growth of various cancer cells, including colon cancer. In the present study, the anti-carcinogenic effects of casticin on human colon cancer and the underlying mechanisms were investigated. The results revealed that casticin significantly induced apoptosis of HT-29, HCT-116, SW480 and Caco-2 cells, induced the accumulation of reactive oxygen species (ROS) and increased the protein levels of apoptosis signal-regulating kinase 1 (ASK1), c-Jun N-terminal kinase (JNK) and B-cell lymphoma 2-interacting mediator of cell death (Bim) in HT-29 cells. Pretreatment with N-acetylcysteine, an antioxidant chemical compound, inhibited the activation of ASK1, JNK and Bim, as well as the apoptosis induced by casticin. Small interfering RNA targeting ASK1 significantly attenuated the induction of JNK and Bim activation and apoptotic cell death by casticin treatment. SP600125, a specific JNK inhibitor, attenuated Bim activation and apoptosis, but did not alter ASK1 phosphorylation levels. In addition, casticin treatment resulted in apoptosis by the same mechanism in HCT-116, SW480 and Caco-2 cells. These results suggest that casticin significantly induced apoptosis by the activation of the ASK1-JNK-Bim signaling cascade and the accumulation of ROS in colon cancer cells.

Mechanisms underlying casticin induced apoptosis of hepatic stellate cells

AIM: To investigate the effect of casticin on apoptosis of hepatic stellate cells (HSCs) in vitro and the possible mechanisms involved.

METHODS: Rat HSC-T6 cells were cultured in high-glucose DMEM and then treated with different concentrations of casticin (0, 0.5, 1.0, and 2.0 μmol/L) for 12, 24 and 48 h. HSC-T6 apoptosis was identified by flow cytometry (FCM) and agarose gel electrophoresis. The mRNA expression of apoptosis-related genes Fas/FasL and Bcl-2 was examined by RT-PCR. The expression of Caspase3 was studied by immunocytochemical staining assay (SABC).

RESULTS: Casticin treatment significantly increased the apoptosis of HSC-T6 in a dose- and time-dependent manner compared with the control group (P < 0.01). The highest apoptosis rate was observed in HSC-T6 cells treated with 2.0 μmol/L of casticin for 48 h (55.70% ± 5.56%). An oligonucleosomal DNA ladder was demonstrated by SABC, indicating DNA break in HSC-T6 cells. The expression of Fas/FasL mRNA was increased, while expression of Bcl-2 mRNA was reduced. After HSC-T6 cells were treated with casticin at concentrations of 0.5, 1.0, and 2.0 μmol/L for 48 h, the positive rates of Caspase3 protein expression were 12.78% ± 0.74%, 41.00% ± 1.51% and 71.33% ± 2.68%, respectively. Casticin treatment significantly increased Caspase3 protein expression in a dose- and time-dependent manner compared with the control group (P < 0.001).

CONCLUSION: Casticin induced apoptosis of HSC-T6 cells may involve mitochondrial pathways and Bcl-2 family proteins. Casticin might be a potential Chinese medical component for inhibiting liver fibrosis.

Casticin induces caspase-mediated apoptosis via activation of mitochondrial pathway and upregulation of DR5 in human lung cancer cells

OBJECTIVE

To assess if casticin induces caspase-mediated apoptosis via activation of mitochondrial pathway and upregulation of DR5 in human lung cancer cells.

METHODS

Human non-small-cell lung carcinoma cell lines H460, A549 and H157 were cultured in vitro. The cytotoxic activities were determined using MTT assay. The apoptotic cells death was examined by flow cytometry using PI staining and DNA agarose gel electrophoresis. The activities of caspase-3, -8 and -9 were measured via ELISA. Cellular fractionation was determined by flow cytometry to assess release of cytochrome c and the mitochondrial transmembrane potential. Bcl-2/Bcl-XL/XIAP/Bid/DR5 and DR4 proteins were analyzed using western blot.

RESULTS

The concentrations required for a 50% decrease in cell growth (IC(50)) ranged from 1.8 to 3.2 μM. Casticin induced rapid apoptosis and triggered a series of effects associated with apoptosis by way of mitochondrial pathway, including the depolarization of the mitochondrial membrane, release of cytochrome c from mitochondria, activation of procaspase-9 and -3, and increase of DNA fragments. Moreover, the pan caspase inhibitor zVAD-FMK and the caspase-3 inhibitor zDEVD-FMK suppressed casticin-induced apoptosis. In addition, casticin induced XIAP and Bcl-XL down-regulation, Bax upregulation and Bid clearage. In H157 cell line, casticin increased expression of DR5 at protein levels but not affect the expression of DR4. The pretreatment with DR5/Fc chimera protein effectively attenuated casticin-induced apoptosis in H157 cells. No correlation was found between cell sensitivity to casticin and that to p53 status, suggesting that casticin induce a p53-independent apoptosis.

CONCLUSIONS

Our results demonstrate that casticin induces caspase-mediated apoptosis via activation of mitochondrial pathway and upregulation of DR5 in human lung cancer cells.

Casticin inhibits epithelial-mesenchymal transition of liver cancer stem cells of the SMMC-7721 cell line through downregulating Twist

The existence of cancer stem cells (CSCs) is central to the pathogenesis and therapeutic target of human hepatocellular carcinoma. The aim of this study was to investigate the effects of casticin on epithelial-mesenchymal transition (EMT) of liver cancer stem cells (LCSCs) derived from the SMMC-7721 cell line. Our results demonstrated that CD133⁺ sphere-forming cells (SFCs) sorted from the SMMC-7721 cell line not only possessed a higher capacity to form tumor spheroids in vitro, but also had a greater potential to form tumors when implanted in Balb/c-nu mice, indicating that CD133⁺ SFCs possessed similar traits to LCSCs. Casticin increased the expression levels of E-cadherin and decreased those of N-cadherin in LCSCs. Treatment of LCSCs with casticin for 48 h also decreased the levels of the EMT-associated transcription factor, Twist. Overexpression of Twist attenuated the casticin-induced regulation of E-cadherin and N-cadherin protein expression, as well as the EMT capacity of LCSCs. In conclusion, CD133⁺ SFCs of the SMMC-7721 cell line may represent a subpopulation of LCSCs with the characteristics of EMT. Furthermore, casticin targeted LCSCs through the inhibition of EMT by downregulating Twist.

Casticin induces ovarian cancer cell apoptosis by repressing FoxM1 through the activation of FOXO3a

Casticin, a polymethoxyflavone, is reported to have anticancer activities. The aim of the present study was to examine the molecular mechanisms by which casticin induces apoptosis in ovarian cancer cells. The human ovarian cancer cell lines SKOV3 and A2780 were cultured in vitro. Various molecular techniques, including histone/DNA enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase chain reaction (RT-PCR), western blot analysis and gene transfection, were used to assess the expression of FOXO3a and forkhead box protein M1 (FoxM1) in casticin-treated ovarian cancer cell lines. Casticin-induced apoptotic cell death was accompanied by the activation of transcription factor FOXO3a, with a concomitant decrease in the expression levels of FoxM1 and its downstream target factors, namely survivin and polo-like kinase 1 (PLK1), and an increase in p27^KIP1. A small inhibitory RNA (siRNA) knockout of FoxM1 potentiated casticin-induced apoptosis in ovarian cancer cells. Silencing FOXO3a expression using siRNA increased FoxM1 expression levels and clearly attenuated the induction of apoptosis by casticin treatment. These results show that casticin-induced apoptosis in ovarian cancer may be caused by the activation of FOXO3a, leading to FoxM1 inhibition.

Aqueous extract of Vitex trifolia L. (Labiatae) inhibits LPS-dependent regulation of inflammatory mediators in RAW 264.7 macrophages through inhibition of Nuclear Factor kappa B translocation and expression

ETHNOPHARMACOLOGICAL RELEVANCE

Vitex trifolia L. (Labiatae), a widespread tree found from the Asia-Pacific to the east Africa regions is used in the traditional medicine of the Pacific islands to treat inflammatory-associated conditions.

AIM OF THE STUDY

We herein evaluated its in vitro regulatory effects on the expression profile of lipopolysaccharide (LPS)-induced inflammatory genes focusing on regulation of chemokines C-X-C motif 10 (CXCL-10) and C-C motif ligand 3 (CCL-3) and cyclo-oxygenase (COX)-2. Furthermore, the plant effect on the LPS-mediated activation of Nuclear Factor kappa B (NF-κB) was also studied.

MATERIALS AND METHODS

Aqueous extract of Vitex trifolia leaves was prepared and evaluated for its effect on LPS-induced stress and toxicity-related genes in RAW 264.7 macrophage cells using RT(2) Profiler Polymerase Chain Reaction (PCR) Array System. Effects of the extract on LPS-induced chemokines CCL-3 and CXCL-10, COX-2, and NF-κB p50 and p65 mRNA levels were also studied using Reverse Transcription quantitative PCR (RT-qPCR) technique. Translocation of the nuclear factor was further assessed by measuring its nuclear p65 subunit via an ELISA-based TransAM method.

RESULTS

Vitex trifolia extract at 5000μg/ml exerted a significant inhibitory effect on the expression of various LPS-induced inflammatory genes in RAW 264.7 cells after 8h of incubation time. Using RT-qPCR, this anti-inflammatory effect was further confirmed by significant inhibition of CCL-3 and CXCL-10 mRNA production in LPS-stimulated RAW 264.7 cells upon treatment with 2500μg/ml of Vitex trifolia extract. Furthermore, the inhibitory activity of this plant on LPS-induced COX-2 mRNA was also observed at a concentration of 2500μg/ml in a time-dependent manner. TransAM assays showed that LPS-induced NF-κB translocation was also inhibited by Vitex trifolia extract even at a concentration of extract as low as 250μg/ml. RT-qPCR assays showed that aqueous extract of Vitex trifolia leaves had a significant inhibitory activity on LPS-induced p50 mRNA synthesis. Interestingly, however, no effect on p65 subunit mRNA expression was observed. Moreover, PCR array analysis showed that LPS-induced inflammatory and apoptosis genes under NF-κB control are also repressed by the extract.

CONCLUSION

The anti-inflammatory properties of Vitex trifolia extract seem associated with inhibition of NF-κB translocation through a reduction in the expression level of NF-κB p50 but interestingly not p65 subunit mRNA. The regulatory effects of Vitex trifolia on NF-κB and consequently on inflammation mediators such as chemokines CCL-3 and CXCL-10, and COX-2 provide new evidence of its efficacy and emphasise its high potential therapeutic value. However, further in vivo experiments are still required to validate its utilization as a remedy against inflammatory diseases.

Quantitative determination and pharmacokinetic study of casticin in rat plasma by liquid chromatography-mass spectrometry

A specific and sensitive liquid chromatography-mass spectrometry method has been developed and validated for identification and quantification of casticin in rat plasma after oral and intravenous administrations. Kaempferol was employed as an internal standard (IS). Liquid-liquid extraction using dichloromethane was applied to extract the casticin and the internal standard from plasma. Chromatographic separation was achieved on a Zorbax SB C(18) column (100 mm × 3.0 mm, i.d.: 3.5 μm) with a mobile phase of methanol: 0.05% formic acid aqueous solution (60:40, v/v) at a flow rate of 0.4 mL/min for 10 min. The detection was performed by selected ion monitoring (SIM) mode via positive electrospray ionization (ESI) interface. The lower limit of detection (LLOD) was 7 ng/mL (S/N=5). The calibration curves were linear (r>0.9996) over the concentration range from 14.06 to 7187 ng/mL. Intra-day and inter-day precisions (RSD%) were within 10% and accuracy (RE%) ranged from -8.2% to 1.0%. The extraction recovery at three quality control (QC) concentrations ranged from 91% to 102%. The validated method was successfully applied to the pharmacokinetic study of casticin after both an oral and an intravenous administrations to rats and the absolute bioavailability is 45.5 ± 11.0%.

Casticin-induced apoptosis involves death receptor 5 upregulation in hepatocellular carcinoma cells

AIM: To investigate the apoptotic activities of casticin in hepatocellular carcinoma (HCC) cells and its molecular mechanisms.

METHODS: PLC/PRF/5 and Hep G2 cell lines were cultured in vitro and the inhibitory effect of casticin on the growth of cells was detected by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolim bromide (MTT) assay. The apoptotic cell death was examined using the cell apoptosis enzyme linked immunosorbent assay (ELISA) detection kit, flow cytometry (FCM) after propidium iodide (PI) staining and DNA agarose gel electrophoresis. The caspase activities were measured using ELISA. Reactive oxygen species (ROS) production was evaluated by FCM after dichlorodihydrofluorescein diacetate (DCFH-DA) probe labeling. Intracellular glutathione (GSH) content was measured using a glutathione assay kit. The expression of death receptor (DR)4 and DR5 proteins was analyzed by Western blotting and FCM.

RESULTS: Casticin significantly inhibited the growth of human HCC (PLC/PRF/5 and Hep G2) cells in a dose-dependent manner (P < 0.05). Casticin increased the percentage of the sub-G1 population in HCC cells in a concentration-dependent manner. The potency of casticin to PLC/PRF/5 cells was higher than that of 5-flurouracil (26.8% ± 4.8% vs 17.4% ± 5.1%) at 10 μmol/L for 24 h. Casticin increased the levels of Histone/DNA fragmentation and the levels of active caspase-3, -8 and -9 in a concentration-dependent manner (P < 0.05). Treatment with 30 μmol/L casticin for 24 h resulted in the formation of a DNA ladder. Casticin reduced the GSH content (P < 0.05), but did not affect the level of intracellular ROS in PLC/PRF/5 and Hep G2 cells. The thiol antioxidants, acetylcysteine (NAC) and GSH restored GSH content and attenuated casticin-induced apoptosis. In contrast, the nonthiol antioxidants, butylated hydroxyanisole and mannitol failed to do so. In the HCC cells treated with casticin for 24 h, DR5 protein level was increased. The expression of DR5 protein induced by casticin was inhibited by NAC. Pretreatment with DR5/Fc chimera protein, a blocking antibody, effectively attenuated the induction of apoptosis by casticin.

CONCLUSION: Casticin-induced apoptosis of HCC cells is involved in GSH depletion and DR5 upregulation.

Inhibitory effects of casticin on migration of eosinophil and expression of chemokines and adhesion molecules in A549 lung epithelial cells via NF-κB inactivation

ETHNOPHARMACOLOGICAL RELEVANCE

The fruits of Vitex rotundifolia L. have long been used for the treatment of inflammation of the respiratory tract in East Asia.

AIM

To determine if casticin, one of the constituents of Vitex rotundifolia L., has anti-allergic and anti-inflammatory effects in asthma.

MATERIALS AND METHODS

The in vitro anti-inflammatory activity of casticin was studied in A549 human type II-like epithelial lung cells using an eotaxin inhibition assay. Additionally, its effects on eotaxin, regulated on activation normal T cell expressed and secreted (RANTES), vascular cell adhesion molecule (VCAM)-1, and inter-cellular adhesion molecule (ICAM)-1 expression were investigated by real time-polymerase chain reaction (real time-PCR). The inhibition of nuclear factor κB (NF-κB) activity in the presence of casticin was determined by analyzing confocal microscopy images of fluorescence immunocytochemical analysis while the suppression of inhibitory κB (IκB)-α phosphorylation was studied using Western blot analysis. Finally, the inhibitory effect of casticin on eosinophil migration toward prestimulated A549 cell media was measured using the human eosinophilic leukemia cell line.

RESULTS AND DISCUSSION

Casticin significantly suppressed eotaxin production in cytokine activated A549 lung epithelial cells. Casticin also suppressed the mRNA expression levels of eotaxin, RANTES, VCAM-1, and ICAM-1, which subsequently contributed to the inhibition of eosinophil migration. Furthermore, casticin inhibited IκB-α phosphorylation and nuclear translocation of p65 in A549 cells.

CONCLUSION

Casiticin inhibited the eosinophil migration and activity of chemokines and adhesion molecules involved in the inflammatory process of asthma by suppressing the NF-κB pathway. These results suggest that casticin has the potential for use in the treatment of allergic asthma.

Characterisation of the anti-inflammatory potential of Vitex trifolia L. (Labiatae), a multipurpose plant of the Pacific traditional medicine

AIM OF THE STUDY

Vitex trifolia L. (Labiatae) is a plant commonly employed against Ciguatera Fish Poisoning (CFP) in the Pacific region. Here, the anti-inflammatory potential of an aqueous extract of Vitex trifolia leaves was evaluated by monitoring its effects on the modulation of cytokines, the mediators of inflammation, as well as on the expression profiles of inducible nitric oxide synthase (iNOS) which produces the free radical nitric oxide (NO).

MATERIALS AND METHODS

We prepared an aqueous extract from Vitex trifolia leaves and evaluated its anti-inflammatory potency by monitoring its effect on the lipopolysaccharide (LPS)-induced cytokines and iNOS mRNA over-production in RAW 264.7 macrophages using quantitative Polymerase Chain Reaction (qPCR) and Enzyme-Linked Immunosorbent Assay (ELISA) methods.

RESULTS

Aqueous extract of Vitex trifolia leaves showed significant dose- and time-dependent inhibitory activity on interleukin (IL)-1 beta, IL-6 and iNOS mRNA synthesis, but slight effect on tumor necrosis factor (TNF)-alpha, all of which are involved in the inflammatory response. Moreover, the plant extract seemed to induce the LPS-dependent IL-10 anti-inflammatory cytokine. These results were further confirmed by ELISA using specific antibodies to mouse IL-6, IL-10 and TNF-alpha.

CONCLUSION

The anti-inflammatory effects of Vitex trifolia could validate its utilization as a traditional remedy against CFP and emphasises its potential therapeutic value against other inflammatory diseases. Therefore, this plant is a promising candidate for further screening of its active compounds through activity-guided fractionation.

Casticin induces leukemic cell death through apoptosis and mitotic catastrophe

Casticin, a component from Vitex rotundifolia, widely used as an anti-inflammatory agent in Chinese traditional medicine, was reported to have anti-tumor activities. This study aims to examine the anti-leukemic activity of casticin on leukemia cells and its molecular mechanism. Cell viability was measured by MTT method; apoptosis and cell cycle arrest were determined by flow cytometry, AV-PI assay, and DNA fragmentation assay. Western blot were performed to measure the protein expression level. The cell morphology alteration was detected with immunofluorescent analysis and DAPI nuclear staining. Our results showed that the proliferation of leukemia cells, including K562, Kasumi-1, and HL-60, were inhibited by casticin in a time- and dose-dependent manner. The IC50, determined after 48 h incubation, was 5.95 microM, 4.82 microM, and 15.56 microM for K562, HL-60, and Kasumi-1, respectively. The cell cycle analysis demonstrated casticin treatment resulted in a significant G2/M accumulation, concomitant with upregulation of P21waf1 and P27kip1. The percentage of cells in G2/M increased with time of exposure and reached to its climax (75.3%) at 12 h after casticin treatment, and subsequently declined to 27% at 48 h. We found that casticin treatment induced remarkable apoptosis, evidenced by increased percentage of AV-positive PI-negative cells as well as the cleavage of PARP and caspase 3. In addition, DNA fragmentation assay showed the typical apoptotic DNA ladder in casticin-treated K562 cells. Mitotic catastrophe and decreased polymeric tubulin can also be observed in casticin-treated K562 cells. In addition, we found that PI3K/AKT pathway was activated; Ly294002, a PI3K/AKT specific inhibitor, can enhance the anti-leukemic effect of casticin. Taken together, these results demonstrated that casticin induced leukemic cell death via apoptosis and mitotic catastrophe, and could synergize with PI3K/AKT inhibitor, suggesting that casticin could be a promising therapeutic agent against leukemia.