Excoecarianin, Isolated from Phyllanthus urinaria Linnea, Inhibits Herpes Simplex Virus Type 2 Infection through Inactivation of Viral Particles.

Phyllanthus urinaria Linnea (Euphorbiaceae) is one of the traditional medicinal plants widely used by oriental people to treat various diseases. We have previously demonstrated that the acetone extract of P. urinaria inhibits herpes simplex virus type 2 (HSV-2) but not HSV-1 infection. In a continuing effort to clarify the antiviral mechanisms of P. urinaria, we isolated the pure compound excoecarianin from the whole plant of P. urinaria through acetone extraction, and investigated its anti-HSV-1 and HSV-2 activities. Our results indicated that excoecarianin protected Vero cells from HSV-2 but not HSV-1 infection, and its 50% inhibitory concentration (IC(50)) was 1.4 ± 0.1 µM. The antiviral effective concentration of excoecarianin did not affect the viability or the morphology of Vero cells. Although excoecarianin inhibited HSV-2 infection, the inhibitory effect, however, was most prominent when excoecarianin was concurrently added with the virus. Pretreatment of Vero cells with excoecarianin with removal of the drug prior to infection did not yield any antiviral effects, and the same observation was made for post viral entry treatment. Subsequent studies revealed that excoecarianin inactivated HSV-2 virus particles to prevent viral infection. A synergistic antiviral effect against HSV-2 was also observed when Vero cells were treated with a combination of acyclovir (ACV) and excoecarianin. These results suggested that excoecarianin merits to be further explored as an entry inhibitor against HSV-2 and could potentially be investigated for combinatorial drug treatment with nucleoside analogues such as ACV in therapeutic management of HSV-2 infection.

Influenza A (H(1)N(1)) Antiviral and Cytotoxic Agents from Ferula assa-foetida.

Two new sesquiterpene coumarins, designated 5'-acetoxy-8'-hydroxyumbelliprenin (1) and 10'R-acetoxy-11'-hydroxyumbelliprenin (2), and a new diterpene, 15-hydroxy-6-en-dehydroabietic acid (3), along with 27 known compounds, were isolated from a CHCl(3)-soluble extract of Ferula assa-foetida through bioassay-guided fractionation. The structures of the new metabolites 1-3 were identified by spectroscopic data interpretation and by the Mosher ester method. Compounds 4 and 6-13 showed greater potency against influenza A virus (H(1)N(1)) (IC(50) 0.26-0.86 microg/mL) than amantadine (IC(50) 0.92 microg/mL), and 11 exhibited the best potency (IC(50) 0.51, 2.6, and 3.4 microg/mL) of these compounds against the HepG2, Hep3B, and MCF-7 cancer cell lines, respectively.

Sheng-Ma-Ge-Gen-Tang inhibited Enterovirus 71 infection in human foreskin fibroblast cell line.

ETHNOPHARMACOLOGICAL RELEVANCE: Sheng-Ma-Ge-Gen-Tang (SMGGT), a popular prescription of Chinese traditional medicine, has been used to manage measles infection of children for thousands of years. There are evidences to presume a wider spectrum of antiviral activity of SMGGT. However, SMGGT has not been proven to have activity against EV71 infection. AIM OF THE STUDY: We tested the hypothesis that SMGGT could inhibit cytotoxic effect of EV71. MATERIALS AND METHODS: Human foreskin fibroblast cell line was used for viral culture. Cytotoxicity was examined by XTT assay. RESULTS: SMGGT could inhibit cytopathy induced by EV71 when given before (p<0.0001), in association with (p<0.0001), or after viral infection (p<0.0001). SMGGT was effective (IC(50): 0.21 microg/ml) and safe (SI: more than 24,000). SMGGT could inhibit viral attachment (p<0.0001) and penetration (p<0.0001). EV71 infection could induce cellular interferon production (p<0.0001). However, SMGGT affected neither the virus-induced (p=0.9913), nor the constitutional interferon production (p>0.05). Therefore, SMGGT had direct anti-viral activity not mediated by interferon. CONCLUSIONS: SMGGT was effective on management of the disease induced by EV71 infection.

A water extract of Pueraria lobata inhibited cytotoxicity of enterovirus 71 in a human foreskin fibroblast cell line.

Enterovirus 71 (EV71) can cause brain encephalitis and mortality. However, effective vaccines or chemotherapeutic agents are not yet available. We tested the hypothesis that Pueraria lobata could inhibit the cytotoxic effect of EV71 in a human foreskin fibroblast cell line by the XTT method. Our results showed that the water extract of P. lobata could inhibit cytopathy induced by EV71 when given before (p < 0.0001), simultaneously with (p < 0.0001), or after viral infection (p < 0.0001). Water extract of P. lobata was effective and its minimal concentration that inhibited 50% of the cytopathic effect (IC50) was 0.028 microg/mL. P. lobata was also safe with a selectivity index greater than 107,000. Water extract of P. lobata appeared to inhibit viral attachment (p < 0.0001) and penetration (p < 0.0001). The anti-EV71 activity of the water extract of P. lobata was not mediated by interferons. In conclusion, the water extract of P. lobata was effective in the management of the disease induced by EV71 infection.

Artemisia capillaris inhibited enterovirus 71-induced cell injury by preventing viral internalization.

Artemisia capillaris (A. capillaris) is a common herbal drug used for thousands years in ancient China. A. capillaris has been empirically used to manage hand-foot-mouth disease (HFMD), which is commonly caused by enterovirus 71 (EV71). EV71 can cause meningoencephalitis with mortality and neurologic sequelae without effective management. It is presently unknown whether A. capillaris is effective against EV71 infection. To test the hypothesis that it could protect cells from EV71-induced injury, a hot water extract of A. capillaris was tested in human foreskin fibroblast cells (CCFS-1/KMC) and human rhabdomyosarcoma cells (RD cells) by plaque reduction assay and flow cytometry. Inhibition of viral replication was examined by reverse quantitative RT-PCR (qRT-PCR). Its effect on translations of viral proteins (VP0, VP1, VP2, protease 2B and 3AB), and apoptotic proteins were examined by western blot. A. capillaris was dose-dependently effective against EV71 infection in both CCFS-1/KMC cells and RD cells by inhibiting viral internalization. However, A. capillaris was minimally effective on viral attachment, VP2 translation, and inhibition of virus-induced apoptosis. Further isolation of effective molecules is needed. In conclusion, A. capillaris has anti-EV71 activity mainly by inhibiting viral internalization. A. capillaris would be better to manage EV71 infection in combination with other agents.

Bupleurum kaoi inhibits Coxsackie B virus type 1 infection of CCFS-1 cells by induction of type I interferons expression.

Coxsackie B virus type 1 (CVB1) infection is known to cause high morbidity and mortality in children, however, there is no effective drug for treating this disease. The present study aimed to examine the antiviral activity of Bupleurum kaoi (BK), a popular herbal drug for treating viral and bacterial infections, against CVB1 infection and its mechanisms of action. Our data showed that BK neutralized the CVB1-induced cytopathic effect in human neonatal foreskin fibroblast cell line (CCFS-1/KMC), with IC50 and EC50 values around 12.38 microg/ml and 50.93 microg/ml, respectively. Its CC50 and SI values were 883.56 microg/ml and 17.34, respectively. These results suggest that BK possessed anti-CVB1 activity, and showed no effect on CCFS-1 cell viability and growth at concentration 250 microg/ml. The time-of-addition studies showed that BK (50, 100 and 200 microg/ml) added at various time of preinfection (-1 to -3 h), coinfection (0 h) and postinfection (1-3 h) could inhibit CVB1 infection. Interestingly, BK also showed an inhibition on viral replication through the induction of IFN-alpha/beta expression. In conclusion, BK possessed antiviral activity against CVB1 infection. It interfered the early stage of viral replication and viral replication after infection through the induction of type I interferon expression.

The in vitro activity of geraniin and 1,3,4,6-tetra-O-galloyl-beta-D-glucose isolated from Phyllanthus urinaria against herpes simplex virus type 1 and type 2 infection.

Phyllanthus urinaria Linnea (Euphorbiaceae) is a widely used traditional medicinal plant by oriental countries and has been reported to possess various biological activities. Previously, the acetone extract from Phyllanthus urinaria was found to inhibit herpes simplex virus (HSV) infection. In this study, geraniin and 1,3,4,6-tetra-O-galloyl-beta-D-glucose (1346TOGDG), both of which were isolated from the acetone extract of Phyllanthus urinaria, were examined for their activity against HSV-1 and HSV-2 in vitro. Results showed that geraniin actively suppressed HSV-2 infection, whereas 1346TOGDG effectively inhibited HSV-1 infection. The 50% inhibitory concentration (IC(50)) was 18.4+/-2.0 microM for geraniin against HSV-2 infection, and 19.2+/-4.0 microM for 1346TOGDG against HSV-1. No toxic effect towards the host cell was observed at the antiviral concentrations. In conclusion, geraniin and 1346TOGDG were found to inhibit HSV-1 and HSV-2 multiplication at different magnitudes of potency.

Sho-saiko-to (Xiao-Chai-Hu-Tang) and crude saikosaponins inhibit hepatitis B virus in a stable HBV-producing cell line.

To search for an effective antiviral agent, this study tested the hypothesis that sho-saiko-to (Xiao-Chai-Hu-Tang) and crude saikosaponins possess the activity directly against HBV and could affect the expressions of viral antigens, HBeAg and HBsAg, in HepG(2) 2.2.15 cell model. The viral amount and viral antigens in the suspension were estimated by quantitative real time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. The results showed that sho-saiko-to could inhibit the production of HBV (p < 0.0001), 20 microg/ml sho-saiko-to was efficacious at day-3 of treatment and 10 microg/ml at day-6. The calculated IC(50) and CC(50) of sho-saiko-to were 55.76 microg/ml and 372 microg/ml, respectively, with a selectivity index of 6.67. Crude saponin of B. chinense could also inhibit the replication of HBV (p < 0.0001). Owing to the anti-neoplastic activity of sho-saiko-to and saikosaponin, their calculated CC(50) and selectivity index might be under-estimated. Sho-saiko-to also decreased the expression of HBeAg with the minimal effective concentration of 20 microg/ml. Sho-saiko-to contained too little saikosaponin. Therefore, the anti-HBV activity of sho-saiko-to might not be mediated by saikosaponin. Sho-saiko-to could be supplementary to nucleotide analogues to minimize the recurrence of viremia after its discontinuation.

Flos Farfarae Inhibits Enterovirus 71-Induced Cell Injury by Preventing Viral Replication and Structural Protein Expression.

Enterovirus 71 (EV71) infection can cause airway symptoms, brainstem encephalitis, neurogenic shock, and neurogenic pulmonary edema with high morbidity and mortality. There is no proven therapeutic modality. Flos Farfarae is the dried flower bud of Tussilago farfara L. that has been used to manage airway illnesses for thousands of years. It has neuro-protective activity and has been used to manage neuro-inflammatory diseases. However, it is unknown whether Flos Farfarae has activity against EV71-induced neuropathy. The current study used both human foreskin fibroblast (CCFS-1/KMC) and human rhabdomyosarcoma (RD) cell lines to test the hypothesis that a hot water extract of Flos Farfarae could effectively inhibit EV71 infection. The authenticity of Flos Farfarae was confirmed by HPLC-UV fingerprint. Through plaque reduction assays and flow cytometry, Flos Farfarae was found to inhibit EV71 infection ([Formula: see text]). Inhibition of viral replication and protein expression were further confirmed by reverse transcription polymerase chain reaction (RT-PCR) and quantitative RT-PCR (qRT-PCR), and western blot, respectively. The estimated IC[Formula: see text]s were 106.3[Formula: see text][Formula: see text]g/mL in CCFS-1/KMC, and 15.0[Formula: see text][Formula: see text]g/mL in RD cells. Therefore, Flos Farfarae could be beneficial to inhibit EV71 infection by preventing viral replication and structural protein expression.

Anti-proliferative effect of apigenin and its apoptotic induction in human Hep G2 cells.

Apigenin, a common dietary flavonoid abundantly present in fruits and vegetables, is believed to possess preventive and therapeutic potential against cancers. In this study, the anti-hepatoma property of apigenin was evaluated on three different human hapatoma cells, namely Hep G2, Hep 3B, and PLC/PRF/5 cells. Results showed that apigenin exhibited a significant growth inhibition against the three selected hepatoma cell lines but not the normal murine liver BNL CL.2 cells. Interestingly, it was shown to possess a similar potency as a commercial anti-hepatoma agent 5-flurouracil (5-FU: positive control) against Hep G2 cells, with IC50 value of 8.02+/-1.30 microg/ml. Therefore, we conducted our study further to investigate the cellular mechanism of apigenin effect on Hep G2 cell death. Using DNA ladder and flow cytometric analysis, apigenin was found to induce apoptosis in Hep G2 cells. It also increased the accumulation of p53 and further enhanced the level of p21/WAF1. Together, it was shown that the apoptosis induced by apigenin in Hep G2 cells was possibly mediated through the p53-dependent pathway and the induction of p21 expression, which was probably associated with the cell cycle arrest in G2/M phase. The present study concludes that the anti-hepatoma activity of apigenin is as effective as 5-FU and its apoptotic mechanism might be mediated through the p53-dependent pathway and the induction of p21 expression.

Antiproliferative and apoptotic effects of tetrandrine on different human hepatoma cell lines.

Tetrandrine (TET), a bis-benzylisoquinoline alkaloid isolated from the dried root of Hang-Fang-Chi (Stephania tetrandra S. Moore), is well known to possess activities including antioxidant, anti-inflammation, anti-fibrotic and anticancer. It is used clinically to treat hypertension and silicosis. In the present study, the anti-proliferative and apoptotic effects of TET were evaluated on three different hepatoma cell lines, namely Hep G2, PLC/PRF/5 and Hep 3B. Using XTT assay, results showed that the IC50 values of TET were 4.35 microM for Hep G2, 9.44 microM for PLC/PRF/5 and 10.41 microM for Hep 3B cells. The CC50 of TET against BNL-CL.2 mouse normal liver cells was 31.12 microM. Interestingly, TET exhibited a lower IC50 value and better selectivity against Hep G2 and PLC/PRF/5 cells than cisplatin. Microscopic observation study, DNA fragmentation assay and flow cytometric analysis further supported apoptotic effect of TET on both PLC/PRF/5 and Hep 3B cells. The cell cycle of PLC/PRF/5 treated with TET appeared to arrest at G2/M phase in a dose-dependent manner, whereas no effect was noted on the cell cycle of Hep 3B cells. The present study concludes that TET exhibited anti-proliferative effect on Hep G2, PLC/PRF/5 and Hep 3B cells in a dose-dependent manner. TET also possesses a lower IC50 and better SI value than cisplatin against Hep G2 and PLC/PRF/5 cells. The effect of TET on cell cycle progression was found to vary with the type of hepatoma cells, suggesting the genetic make-up of the cells play an important role in the response to drug treatment.

Baicalin-induced apoptosis is mediated by Bcl-2-dependent, but not p53-dependent, pathway in human leukemia cell lines.

Acute lymphoblastic leukemia (ALL), especially T-acute lymphoblastic leukemia (T-ALL), is a common childhood malignant neoplastic disorder. Chemotherapy agents, particularly those that can induce apoptosis, are the major intervening strategy in the treatment of ALL. In this study, we investigated in T-ALL cell line, CCRF-CEM, the in vitro cytotoxic effect and the mechanism of action of baicalin, a compound extracted from Scutellaria baicalensis Georgi and S. rivularis Benth (Labiateae). Results demonstrated that baicalin displayed a remarkable cytotoxic effect in CCRF-CEM, with an IC(50) value of 10.6 microg/ml. It triggered apoptotic effect by fragmentizing cellular DNA and arrested the cell cycle at G(0)/G(1) phase. Baicalin (37.5 microg/ml) had not effected the expression of p53 and Fas protein. It was shown to decline the expression of Bcl-2 (22.0 pg/ml), which consequently caused the loss (52.7%) of transmembrane potential (Delta Psi m) in the mitochondria after 72 hours of treatment. Baicalin (37.5 microg/ml) also elevated the amount of cytosolic cytochrome c (19.2 microg/ml), which finally triggered the activation of caspase-3 (50.1 pmol/min). In conclusion, baicalin was found to induce apoptosis in T-ALL cell lines through multiple pathways. This finding encourages further investigation of baicalin in its role as a potential candidate for chemotherapeutic agents in T-ALL.

Histone deacetylase inhibitor up-regulates RECK to inhibit MMP-2 activation and cancer cell invasion.

Histone deacetylase (HDAC) inhibitors are known to exert antimetastatic and antiangiogenic activity in vitro and in vivo. RECK is a membrane-anchored glycoprotein that negatively regulates matrix metalloproteinases (MMPs) and inhibits tumor metastasis and angiogenesis. In this study, we test the possibility that HDAC inhibitor may increase RECK expression to inhibit MMP activation and cancer cell invasion. Our results showed that trichostatin A (TSA) up-regulated RECK via transcriptional activation in CL-1 human lung cancer cells. Flow cytometric analysis demonstrated that RECK protein on cell surface was increased after treatment of TSA. Moreover, up-regulation of RECK expression by TSA attenuated MMP-2 activity. To explore whether HDAC inhibitor-induced inhibition of MMP-2 activation is indeed mediated via RECK, we used small interference RNA (siRNA) to block RECK expression and found that inhibition of RECK by siRNA abolished the inhibitory effect of TSA on MMP-2 activation. In addition, TSA suppressed the invasive ability of CL-1 cells. Taken together, this study reveals a novel mechanism by which HDAC inhibitors suppress tumor invasion and provides a new strategy for cancer therapy.

Gan-Lu-Siao-Du-yin, a prescription of traditional Chinese medicine, inhibited enterovirus 71 replication, translation, and virus-induced cell apoptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Gan-Lu-Siao-Du-yin (GLSDY) is a prescription of traditional Chinese medicine. GLSDY contains 11 ingredients and is commonly used for endemic diseases. Enterovirus 71 (EV71) is an endemic disease that can cause meningoencephalitis with mortality and neurologic sequelae without any effective management. It is unknown whether GLSDY is effective against EV71 infection. AIM OF THE STUDY: To test the hypothesis that GLSDY can protect cell from EV71-induced injury. MATERIALS AND METHODS: Effects of a hot water extract of GLSDY on EV71 were tested in human foreskin fibroblast cells (CCFS-1/KMC) and human rhabdomyosarcoma cells (RD cells) by plaque reduction assay and flow cytometry respectively. Inhibition of viral replication was further examined by reverse quantitative RT-PCR (qRT-PCR). Its effect on viral protein translation and virus-induced apoptosis were examined by western blot. RESULTS: GLSDY was dose-dependently effective against EV71 infection (p<0.0001) in both CCFS-1/KMC cells and RD cells. GLSDY was highly effective when supplemented after viral inoculation (P<0.0001) with an IC50 of 8.7µg/mL. GLSDY inhibited viral RNA replication (P<0.0001), formation of viral structural proteins (VP0, VP1, VP2 and VP3) and non-structural proteins (protease 2B and 3AB). Furthermore, 300µg/mL GLSDY is effective to inhibit virus-induced apoptosis possibly through direct inhibition of caspase-8 and indirectly by inhibition of Bax. CONCLUSIONS: GLSDY is cheap and readily available to manage EV71 infection by inhibiting viral replication, viral protein formations, and EV71-induced apoptosis.

Induction of RECK by nonsteroidal anti-inflammatory drugs in lung cancer cells.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to exert anti-angiogenic and anti-metastatic activity both in vitro and in vivo. Block of angiogenesis and metastasis by NSAIDs has been found to be mediated partly via suppression of matrix metalloproteinase (MMP) activity. However, the molecular mechanism of this inhibitory action has not been well defined. Recent works demonstrated that a membrane-anchored MMP inhibitor RECK may potently suppress MMP-2 and -9 activity to inhibit angiogenesis and metastasis in vitro and in vivo. In this study, we test the possibility that NSAIDs may up-regulate RECK to inhibit MMP activity. RT-PCR analyses showed that NS398 and aspirin up-regulated RECK mRNA level in CL-1 human lung cancer cells. Additionally, NSAIDs increased RECK protein level as detected by immunoblotting. Since RECK is a membrane-anchored glycoprotein, we also performed immunofluorescent staining to assess the expression of RECK on cell surface. Our results showed that fluorescent intensity of RECK was obviously increased after NSAID treatment. Moreover, induction of RECK by NSAIDs was associated with reduction of MMP-2 activity. We also found that NSAID-activated RECK expression might not be mediated via inhibition of cyclo-oxygenases (COXs) because addition of prostaglandin E(2) (PGE(2)) could not counteract the effect of NSAIDs and overexpression of COX-2 could not down-regulate RECK. Taken together, our results suggest that induction of RECK expression may be one of the mechanisms by which NSAIDs suppress MMP activity to block angiogenesis and metastasis.

Acetone, ethanol and methanol extracts of Phyllanthus urinaria inhibit HSV-2 infection in vitro.

Phyllanthus urinaria Linnea (Euphorbiaceae) is one of the traditional medicinal plants that are widely applied by oriental people, especially by Chinese and Indian, to ameliorate various kinds of ailments. Many biological activities, including anti-hepatitis B virus, anti-Epstein-Barr virus and anti-retroviral reverse transcriptase, of P. urinaria have been reported, but not against herpes simplex virus (HSV). In this study, the anti-HSV-1 and HSV-2 activities of different solvents extracted from P. urinaria were investigated in vitro by plaque reduction assay. Results showed that acetone, ethanol and methanol extracts of P. urinaria inhibited HSV-2 but not HSV-1 infection. The 50% inhibitory concentration against HSV-2 infection (IC50) of acetone, ethanol and methanol extracts was 4.3 +/- 0.5, 5.0 +/ -0.4 and 4.0 +/- 0.9 mcg/ml, respectively. All three extracts showed no cytotoxic effect against Vero cells at concentrations of 10.0 mcg/ml or below. The time-of-addition study demonstrated that these three extracts were only effective when added during the HSV-2 infection which, therefore, suggested that they disturb the initial stage of HSV-2 infection. Furthermore, they can diminish virus infectivity without significantly affecting incubation time and temperature. Therefore, the acetone, ethanol and methanol extracts of P. urinaria were concluded to likely inhibit HSV-2 infection through disturbing the early stage of virus infection and through diminishing the virus infectivity.

Ethanol extract of Polygonum cuspidatum inhibits hepatitis B virus in a stable HBV-producing cell line.

Chronic hepatitis B virus (HBV) infection is endemic in Asia and its consequences are among the major public health problems in the world. Unfortunately, the therapeutic efficacies of present strategies are still unsatisfactory with a major concern about viral mutation. In search of effective antiviral agent, we examined the efficacy of extracts of Polygonum cuspidatum Sieb. et Zucc. (P. cuspidatum) against HBV in HepG2 2.2.15 cells by quantitative real time polymerase chain reaction. The expressions of viral antigens, HBeAg and HBsAg, were also determined by enzyme linked immunosorbent assay. The ethanol extract of P. cuspidatum could inhibit dose-dependently the production of HBV (p<0.0001) with an effective minimal dosage of 10 microg/ml. The water extract of P. cuspidatum might also inhibit the production of HBV at a higher dosage. The expression of HBsAg was significantly increased by both ethanol extract and water extract of P. cuspidatum dose-dependently (p<0.0001) and time-dependently (p<0.0001). Higher dose of water extract of P. cuspidatum (30 microg/ml) could inhibit the expression of HBeAg (p<0.05). The extract of P. cuspidatum might contain compounds that would contribute to the control of HBV infection in the future. However, its promoting effect on the expression of HBsAg and its cytotoxicity should be monitored. Further purification of the active compounds, identification and modification of their structures to improve the efficacy and decrease the cytotoxicity are required.

Apigenin induced apoptosis through p53-dependent pathway in human cervical carcinoma cells.

Apigenin is a widely distributed plant flavonoid and was proposed as an antitumor agent. In this study, we reported for the first time that apigenin inhibited the growth of human cervical carcinoma cells (HeLa) and through apoptotic pathway. The results showed that apigenin significantly decreased the viability of HeLa cells at 37-74 microM and the IC50 value was 35.89 microM. Apigenin-induced apoptosis in HeLa cells was confirmed by DNA fragmentation assay and induction of sub-G1 phase by flow cytometry. Apigenin-treated HeLa cells were arrested at G1 phase, which was associated with a marked increment of the expression of p21/WAF1 protein. The induction of p21/WAF1 appeared to be transcriptionally upregulated and was p53-dependent. In addition, apigenin induced Fas/APO-1 and caspase-3 expression which were also correlated with apoptosis. Apigenin decreased in the protein expression of Bcl-2 protein, which is an anti-apoptotic factor. The conclusion of this study is the apigenin induced p53 expression which caused cell cycle arrest and apoptosis. These findings suggest that apigenin has strong potential for development as an agent for preventing cervical cancer.

New gemacranolides from Eupatorium hualienense.

Phytochemical investigation of Eupatorium hualienense (C. H. Ou, S. W. Chung, C. I. Peng) has resulted in the isolation of the new sesquiterpene lactones 1-5, named eupahualins A-E, along with the known heliangolide eupasimplicin B (6). The structures of the isolated compounds were established through detailed spectral analyses, especially by means of 2D-NMR techniques. Compounds 1-4 and 6 showed significant activities against cell lines of human chronic myelogenous leukemia (K562) and human bone cancer (U2OS).

Yakammaoto inhibits enterovirus 71 infection by reducing viral attachment, internalization, replication, and translation.

Enterovirus 71 (EV71) can cause central nervous system infections with mortality and neurologic sequelae. At present, there is no effective therapeutic modality for EV71 infection. The infection is more common in families with poor socioeconomic status. Therefore, finding a readily available, cost-effective therapeutic modality would be very helpful to these socioeconomically disadvantaged families. Yakammaoto is a cheap and readily available traditional prescription that is proven to have antiviral activity against coxsackievirus B4 (CVB4). CVB4 and EV71 are enteroviruses. In this study, we evaluated the antiviral activity of hot water extract of yakammaoto against EV71. The results of plaque reduction assay and flow cytometry demonstrated that yakammaoto dose dependently inhibited EV71 infection. In addition, reverse transcription-polymerase chain reaction (RT-PCR) and quantitative RT-PCR results showed that yakammaoto reduced viral replication. Western blotting analysis showed that yakammaoto can inhibit viral protein production. Thus, our results suggest that yakammaoto should be considered to manage EV71 infection in the future.