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Plastics are one of the most pervasive materials on Earth, to which humans are exposed daily. Polystyrene (PS) is a common plastic packaging material. However, the impact of PS on human health remains poorly understood. Therefore, this study aimed to identify intestinal damage induced by PS nanoplastics (PS-NPs) in zebrafish larvae which have a high homology with humans. Four days post fertilization (dpf), zebrafish larvae were exposed to 0-, 10-, and 50-ppm PS-NPs for 48 h Initially, to ascertain if 100 nm PS-NPs could accumulate in the gastrointestinal (GI) tract of zebrafish larvae, the larvae were exposed to red fluorescence-labeled PS-NPs, and at 6 dpf, the larvae were examined using a fluorescence microscope. Analysis of the fluorescence intensity revealed that the GI tract of larvae exposed to 50-ppm exhibited a significantly stronger fluorescence intensity than the other groups. Nonfluorescent PS-NPs were then used in further studies. Scanning electron microscopy (SEM) confirmed the spherical shape of the PS-NPs. Fourier-transform infrared spectroscopy (FT-IR) analysis revealed chemical alterations in the PS-NPs before and after exposure to larvae. The polydispersity index (PDI) value derived using a Zetasizer indicated a stable dispersion of PS-NPs in egg water. Whole-mount apoptotic signal analysis via TUNEL assay showed increased apoptosis in zebrafish larval intestines exposed to 50-ppm PS-NPs. Damage to the intestinal tissue was assessed by Alcian blue (AB) and hematoxylin and eosin (H&E) staining. AB staining revealed increased mucin levels in the zebrafish larval intestines. Thin larval intestinal walls with a decrease in the density of intestinal epithelial cells were revealed by H&E staining. The differentially expressed genes (DEGs) induced by PS-NPs were identified and analyzed. In conclusion, exposure to PS-NPs may damage the intestinal barrier of zebrafish larvae due to increased intestinal permeability, and the in vivo gene network may change in larvae exposed to PS-NPs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Crataegus pinnatifida has been famous for its nutritional purpose. However, systematic investigation on the bioactive constituents is still lacking, although this fruit has been reported for its cytotoxic effect before. In this study, two pairs of new lignan enantiomers (1a/1b, 2a/2b), which isolated using chiral chromatographic column from the fruits of C. pinnatifida were studied. The absolute configurations of enantiomers were determined by comparison between the experimental electronic circular dichroism (ECD) and calculated ECD spectra. Among them, 1a/1b exhibited a better cytotoxic effect in hepatocellular carcinoma Hep3B cells with an IC 50 value of 34.97 ± 2.74 and 17.42 ± 0.71 μM, respectively. In addition, 1b induced much more apoptotic, autophagic cells than 1a in Hep3B cells. Furthermore, the underlying mechanism was demonstrated that p38 activation could promote 1b-induced apoptosis and autophagy. Moreover, 1b-induced apoptosis was significantly decreased in the presence of autophagic inhibitor Bafilomycin A1 (Baf A1), suggesting that the induction of autophagy enhanced apoptotic cell death in 1b-treated cells. In general, these findings provide a valuable basis for further understanding the effect of 8-O-4' lignans in C. pinnatifida on cytotoxic effect., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Epidemiological evidence suggests that the etiology and pathogenesis of rheumatoid arthritis (RA) are closely associated with estrogen metabolism and deficiency. Estrogen protects against articular damage. Estradiol replacement therapy ameliorates local inflammation and knee joint swelling in ovariectomized models of RA. The mechanistic basis for the protective role of 17β-estradiol (17β-E2) is poorly understood. Acid-sensing ion channel 1a (ASIC1a), a sodium-permeable channel, plays a pivotal role in acid-induced articular chondrocyte injury. The aims of this study were to evaluate the role of 17β-E2 in acid-induced chondrocyte injury and to determine the effect of 17β-E2 on the level and activity of ASIC1a protein. Results showed that pretreatment with 17β-E2 attenuated acid-induced damage, suppressed apoptosis, and restored mitochondrial function. Further, 17β-E2 was shown to reduce protein levels of ASIC1a through the ERα receptor, to protect chondrocytes from acid-induced apoptosis, and to induce ASIC1a protein degradation through the autophagy-lysosomal pathway. Taken together, these results show that the use of 17β-E2 may be a novel strategy for the treatment of RA by reducing cartilage destruction through down-regulation of ASIC1a protein levels., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Breast cancer is one of the most common cancers diagnosed among women worldwide. Estrogen receptor alpha (ER α ) is a transcriptional factor that plays an important role in the development and progression of breast cancer. Yuanhuatine, a natural daphnane-type diterpenoid extracted from Daphne genkwa , was reported to exhibit significant cytotoxicity against breast cancer cells. However, the underlying mechanism is still unclear. In this study, we evaluated the cytotoxicity of yuanhuatine on two breast cancer cell lines that are ER α -positive and -negative. The results show that yuanhuatine inhibits the growth of ER α -positive cells (MCF-7) with much stronger inhibitory activity (IC 50  = 0.62 µM) compared with positive control tamoxifen (IC 50  = 14.43 µM). However, no obvious cytotoxicity was observed in ER α -negative cells (MDA-MB-231). Subsequent experiment also indicated that yuanhuatine markedly induced mitochondrial dysfunction, leading to apoptosis in MCF-7 cells. Molecular docking studies suggest the potential interactions between yuanhuatine and ER α . Immunofluorescence staining and Western blot analysis indicated that yuanhuatine down-regulated the expression of ER α in MCF-7 cells. MPP, a specific ER α inhibitor, significantly enhanced yuanhuatine-induced mitochondrial dysfunction and apoptosis in MCF-7 cells. On the contrary, the treatment with yuanhuatine causes no apoptosis in MM231 cells. Altogether, in vitro and in silico results suggested that ER α down-regulation was involved in yuanhuatine-induced mitochondrial dysfunction and apoptosis in ER α -positive breast cancer cells. Thus, yuanhuatine could be a potential candidate for treating ER α -positive breast cancer., Competing Interests: The authors declare that they have no conflict of interest., (Georg Thieme Verlag KG Stuttgart · New York.)

Phytochemical investigation of the fruit of Crataegus pinnatifida led to the isolation of four pairs of dihydrobenzofuran neolignan enantiomers (1a/1b-4a/4b) including six new compounds (1a/1b, 2a/2b, 3a and 4a). The enantioseparations of the racemates were achieved successfully by chiral chromatographic column. Their structures were established by comprehensive spectroscopic analyses and the absolute configurations were determined by quantum mechanical calculation of electronic circular dichroism (ECD) spectra. All compounds were evaluated in vitro for their cytotoxicity using human hepatocellular carcinoma Hep3B and HepG2 cells. Among them, it was found that 2a had a selective cytotoxicity against Hep3B cells with IC 50 value of 25.47 μM, while the IC 50 value of its enantiomer 2b on Hep3B cells was 59.37 μM. These results implied that the absolute configurations of 2a and 2b possessed remarkable influences on their cytotoxicity. Further flow cytometry analysis indicated that 2a performed more significant effect on cell apoptosis compared with its enantiomer 2b., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Oxidative stress accompanying excessive accumulation of reactive oxygen species (ROS) and mitochondrial dysfunction leads to the occurrence of neurodegenerative diseases. Our previous study showed that Eclalbasaponin I (EcI), a triterpene saponin isolated from Aralia elata (Miq.) Seem. ( A. elata ), repressed oxidative stress in human neuroblastoma SH-SY5Y cells. However, the detailed mechanism remains unclear. In this study, pretreatment with EcI in SH-SY5Y cells significantly activated the p38-mitogenactivated protein kinase (p38), the extracellular regulated protein kinase (ERK), whereas it did not affect the c-jun NH2 terminal kinases (JNK). In accordance with the initial findings, EcI-induced neuroprotective effect was attenuated by SB203580 (SB, a p38 inhibitor) or FR180204 (FR, an ERK inhibitor), being further confirmed by specific small interfering RNA (siRNA). Inhibition of either p38 or ERK up-regulated the apoptosis induction in EcI- and H 2 O 2 -cotreated cells. Furthermore, p38 or ERK suppression enhanced intracellular and mitochondrial ROS generation, decreased the activities of endogenous antioxidant defences as well as the mitochondrial membrane potential (MMP), resulting in dysfunction of mitochondria. In addition, EcI-induced autophagy and mitophagy were obviously down-regulated when p38 or ERK activation was blocked. Cumulatively, these findings supported that EcI-caused mitophagy contributed to the neuroprotective effect through p38 or ERK activation. Mitophagy induction might be an effective therapeutic intervention in neurodegenerative diseases.

Two 8-O-4'-type neolignan epimers erythro-guaiacylglycerol-β-coniferyl aldehyde ether (1) and threo-guaiacylglycerol-β-coniferyl aldehyde ether (2) were isolated from the stems of Picrasma quassioides. Further chiral separation gave two pairs of enantiomers 1a/1b and 2a/2b. The cytotoxicity assay against hepatocellular carcinoma Hep3B and HepG2 cells was evaluated by MTT assay. The results showed that 1b (IC 50  = 45.56 μM) and 2b (IC 50  = 39.02 μM) had more cytotoxic effect than its enantiomers 1a (IC 50  = 82.66 μM) and 2a (IC 50  = 67.97 μM) in Hep3B cells, respectively. Moreover, 1b and 2b could induce more apoptotic cells as well as higher reactive oxygen species (ROS) generation than 1a and 2a at 50 μM. In addition, a further study on the phosphoinositide 3-kinase (PI3K)/AKT and mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathways was investigated. The results revealed that all compounds had no significant effect on PI3K/AKT pathway, however, 1b and 2b attenuated the relative levels of p-MEK and p-ERK when compared with 1a and 2a. Taken together, the absolute configurations of guaiacylglycerol-β-coniferyl aldehyde ether had an impact on the inhibitory effect on Hep3B cells. The inactivation of MEK/ERK signaling pathway might contribute to apoptosis induction and ROS generation in 1b- and 2b-treated cells., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Four pairs of racemic phenylpropanoids (1a/1b-4a/4b), including five new compounds (1a/1b, 2a, 3a, and 4a) were obtained from the root barks of Ailanthus altissima (Mill.) Swingle. Their structures were determined by comprehensive spectroscopic analyses. The absolute configurations of the enantiomers were determined by comparison of the experimental ECD and OR with the calculated data. The antitumor activity of all isolates was evaluated against two human hepatoma carcinoma cells (HepG2 and Hep3B) in vitro. It was demonstrated that 1a/1b showed potent selective cytotoxicity against HepG2 cells. Additionally, 1a/1b could also induce apoptosis enantioselectively as demonstrated by Hoechst staining experiment., (Copyright © 2018 Elsevier B.V. All rights reserved.)

L-A03 is a dihydroartemisinin derivative and exerts distinct anti-tumor activity in vitro. Previous studies showed that induction of autophagy and deficiency in nitric oxide (NO) generation contributed to apoptotic cell death in L-A03-treated MCF-7 cells. However, the detailed mechanism is still unclear. In this study, the role of mitogen-activated protein kinases (MAPKs) in this apoptotic process was investigated. L-A03 (7.5-30 μM) selectively inhibited the activation of c-Jun N-terminal protein kinase (JNK) with no significant effect on extracellular signal related kinase (ERK) and p38. In addition, the possible mechanism of interaction between JNK and L-A03 was also investigated by molecular docking. In the presence of SP600125, a specific JNK inhibitor, induction of autophagy and apoptosis with L-A03 at 15 μM were elevated, but NO generation was attenuated, indicating that JNK inactivation is essential for apoptotic cell death. Interestingly, autophagy induction and NO generation did not affect the activation of JNK, demonstrating that JNK is upstream to autophagy and NO. Taken together, L-A03-induced JNK inactivation enhances autophagic and apoptotic cell death, but represses the generation of NO. This study provides a new insight on the mechanism of L-A03-induced cell death by targeting JNK., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Eight new phenylpropanoids (1a/1b, 2-4, 5a/5b and 6) including two pairs of enantiomers (1a/1b and 5a/5b), along with a known analogue (7) were isolated from the fruit of Crataegus pinnatifida. Their structures were elucidated using comprehensive spectroscopic methods. Compounds 1a/1b and 5a/5b were separated successfully by chiral chromatographic column. The absolute configurations of enantiomers were determined by comparison between the experimental and calculated electronic circular dichroism (ECD) spectra. The in vitro antitumor activities of the isolates were evaluated against two human hepatocellular carcinoma HepG2 and Hep3B cells. Five compounds (1a/1b, 2-4) exhibited more potent cytotoxicity and their structure-activity relationships were also discussed. Annexin V-FITC/PI staining using flow cytometry was carried out to examine cell apoptosis, and the results showed that compounds 3-4 with the presence of two methoxy groups substituted at C-3' significantly induced apoptosis in HepG2 cells., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Hepatocellular carcinoma (HCC) is a primary malignant tumor with very poor prognosis. To search for more effective compounds for HCC treatment, two new pairs of flavan enantiomers, daphnegiranol C 1 /C 2 (1a/1b) and daphnegiranol D 1 /D 2 (2a/2b), were isolated from the stem bark and roots of Daphne giraldii by using chiral chromatography. MTT assay was applied to evaluate their cytotoxicity against three hepatocarcinoma cell lines (Hep3B, MHCC97H, HepG2) as well as a normal liver cell line L02. The results showed that these compounds preferred to inhibit the growth of Hep3B cells (p53 null). Among them, 2a/2b (the IC 50 value was 4.87 and 3.35 μM, respectively) exhibited a stronger cytotoxic effect than sorafenib (IC 50  = 6.59 μM) in Hep3B cells. A further study demonstrated that 2a/2b could induce apoptotic cell death with an increase in reactive oxygen species (ROS) in Hep3B cells. In addition, the IC 50 values of 2a/2b in HepG2 and MHCC97H cells (both harbored p53 gene) were more than 10-folds greater when compared with Hep3B cells, indicating that 2a/2b selectively exhibited cytotoxicity in p53-null hepatocarcinoma cells. Moreover, inhibition of p53 increased the inhibitory effect in p53-wild hepatocarcinoma cells, as well as apoptotic cells and ROS generation. Taken together, flavan enantiomers 2a/2b selectively induced apoptosis in Hep3B cells because of p53 deficiency., (Copyright © 2018. Published by Elsevier B.V.)

Three pairs of enantiomeric neolignans 1a/1b-3a/3b were isolated from the stems of Picrasma quassioides, and separated successfully by chiral-phase HPLC. Their structures were established by comprehensive spectroscopic analyses as well as ECD spectroscopy. The in vitro cytotoxicity of the isolates was evaluated against human hepatocellular carcinoma HepG2 and Hep3B cells. Among them, 1 and its enantiomers 1a/1b, 3 and 3a/3b displayed similar cytotoxicity in pair-wise comparison against HepG2 and Hep3B cells, and the similar effects of 2 and 2a/2b were found in Hep3B cells. Interestingly, 2a and 2b had different cytotoxic activities on HepG2 cells with IC 50 values of 35.6 μM and 104.4 μM, respectively. In addition, 2 exerted middle cytotoxicity against HepG2 cells with an IC 50 value of 78.6 μM. The different cytotoxicity between enantiomers 2a and 2b attracted our interest. To investigate the underlying mechanisms responsible for the distinct cytotoxicity, we further assessed the effects of 2a and 2b on cell cycle distribution, cell apoptosis and reactive oxygen species (ROS) generation. The results indicated that 2a had more significant effect than 2b on apoptosis induction and ROS generation, but both had no obvious effect on cell cycle of HepG2 cells. It is concluded that the different configurations of 2a/2b determined the enantioselective cytotoxicity on HepG2 cells through apoptosis induction and ROS generation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

One new 1,3-diphenylpropane (1) together with six known analogues (2-7) were firstly isolated from the stem and root bark of Daphne giraldii. Their structures were determined by comprehensive NMR and HRESIMS spectroscopic data analyses. All the isolates were evaluated for their cytotoxicity against two hepatocellular carcinoma cell lines (HepG2 and Hep3B). Among them, compound 5 showed the most significant cytotoxicity against Hep3B cells, with an IC 50 value of 17.21 μM. A further study demonstrated that 5 obviously induced apoptotic cell death as well as the inactivation of nuclear factor kappa B p65 (NF-κB p65) in Hep3B cells. In addition, BAY 11-7082 (BAY), a NF-кB inhibitor, was used to determine the role of NF-кB signaling in 5-treated Hep3B cells. The results suggested that BAY could enhance 5-induced apoptosis of Hep3B cells. In conclusion, the data provided that 5 might be a potential candidate for the treatment of hepatocellular carcinoma through NF-κB inhibition., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Hepatocellular carcinoma (HCC), the most common type of liver cancer, has high morbidity and mortality rates, and its prognosis is poor. The treatment options of HCC are limited by the lack of effective chemotherapy. Therefore, looking for effective drugs with little toxicity is very urgent. The aim of this study was to search for small molecule targeting on liver cancer from Juglans mandshurica, which has been used to treat cancers for a long time in China. Under the guide of anti-hepatoma activity, a new coumarin (1), together with eight reported analogs (2‒9), was isolated from the 75% EtOH extract. The structures of these compounds were determined by 1D and 2D NMR experiments. The absolute configuration of 1 was established by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. The in vitro cytotoxicity experiments on two liver cancer cell lines (HepG2 and Hep3B) showed that compounds 2 and 5 had moderate antitumor activities on both cell lines. And further studies of antitumor mechanisms by the observation of morphological changes and Western blot analyses exhibited that induction of apoptosis might be a possible way that inhibited cell growth.

Pseudolaric acid B (PAB), a diterpene acid isolated from the root bark of Pseudolarix kaempferi Gordon, exerts anti-tumor effects in several cancer cell lines. Our previous study showed that PAB mainly induced senescence via p53-p21 activation rather than apoptosis in suppression of the growth of human lung cancer A549 cells (p53 wild-type). In p53-null human lung cancer H1299 cells, however, PAB caused apoptosis without senescence. In this study we investigated what mechanism was responsible for the switch from senescence to apoptosis in PAB-treated human lung cancer cell lines. Senescent cells were examined by SA-β-gal staining. Glucose uptake and the apoptosis ratio were assessed using a FACScan flow cytometer. Commercial assay kits were used to measure the levels of ATP and lactate. Transfection of siRNA was used to knockdown the expression of p53 or p21. Western blot analysis was applied to measure the protein expression levels. In p53 wild-type A549 cells, PAB (20 μmol/L) caused senescence, and time-dependently increased glucose utilization; knockdown of p53 or p21 significantly decreased the uptake and metabolism of glucose but elevated PAB-induced apoptosis. Inhibition of glucose utilization using a glycolytic inhibitor 2-DG (1 mmol/L) significantly enhanced apoptosis induction. Similar results were observed in another p53 wild-type H460 cells treated with PAB. Opposite results were found in p53-null H1299 cells, where PAB time-dependently decreased glucose utilization, and induced only apoptosis. Our results demonstrate that PAB-induced senescence is associated with enhanced glucose utilization, and lower glucose utilization might contribute to apoptosis induction. Thus, blocking glucose utilization contributes to the switch from senescence to apoptosis, and p53 plays an important role in this process.

Enantiomers account for quite a large percentage of compounds in natural products. Our team is interested in the separation and biological activity of racemic compounds. In this report, four pairs of prenylated flavan enantiomers [(±)-1-(±)-4], including five new compounds, were isolated from the stem and root bark of Daphne giraldii, and separated successfully by using chiral chromatographic column. Their planar structures and absolute configurations were established by comprehensive spectroscopic analyses as well as circular dichroism (CD) spectroscopy. The isolates had a selective cytotoxicity towards hepatic carcinoma cell lines. Among them, new compound (+)-4 showed a more potent inhibitory effect on Hep3B cells with an IC 50 value of 30.3 μM, compared with its racemic mixture 4. Therefore, the action mechanism of (+)-4in vitro was subsequently investigated. The morphological observation and Western blot analysis demonstrated that (+)-4 could markedly induce apoptosis through intrinsic and extrinsic pathways, and also cause autophagy by increasing the phosphorylation of AMP-activated protein kinase (AMPK) in Hep3B cells. After treatment with the autophagic inhibitor bafilomycin A1 (Baf A1), (+)-4-induced apoptosis increased significantly, suggesting that the autophagy induced by (+)-4 performed a protective effect on apoptotic cell death., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Hepatocellular carcinoma (HCC) is the most common type of liver cancer, and treatment options for HCC are limited. In addition, the discovery of new natural compounds with anti-hepatocarcinoma activity is attracting increasing attention. For this reason, phytochemical investigation of Croton crassifolius led to the isolation of 17 diterpenoids, including three new clerodane diterpenoids, named crassifolius A-C (1-3), along with 14 known ones (4-17). Their structures were established by 1D, 2D NMR, HR-ESI-MS, detailed calculated electronic circular dichroism (ECD) spectra and the assistance of quantum chemical predictions (QCP) of 13 C NMR chemical shifts. The cytotoxicities of all these compounds against human liver cancer lines (HepG2 and Hep3B) were determined. Among them, compound 1 exhibited good cytotoxicity with IC 50 value of 17.91μM against human liver tumor cells Hep3B. Following further studies of the anti-tumor mechanism of compound 1-induced cell growth inhibition, we found that compound 1 caused apoptotic cell death in Hep3B cells by detecting morphologic changes and Western blotting analysis., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Three new phenylpropanoids (1-3) together with six known congeners (4-9) were isolated from the bark of Juglans mandshurica Maxim using anti-hepatoma activity as a guide. Their structures were determined by comprehensive NMR and HRESIMS spectroscopic data analyses. All the isolated compounds were evaluated for their growth inhibitory activities against two kinds of liver cancer cell lines (HepG2 and Hep3B). Among them, compound 4 showed moderate cytotoxic activities against HepG2 and Hep3B cell lines with IC 50 values of 58.58 and 69.87μM. Compound 5 exhibited 50% cell death rate in HepG2 and Hep3B cell lines at 63.70 and 46.45μM, respectively. Further observation of morphological changes and Western blot demonstrated that compounds 4 and 5 exhibited their cytotoxic activities through the induction of apoptosis. A structure-activity relationship study suggested that an α, β-unsaturated aldehyde might be the most important functional group., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Timosaponin AIII (AIII), a steroidal saponin isolated from Anemarrhena asphodeloides Bge. Our study showed that AIII induced both apoptosis and autophagy, and autophagy inhibited apoptosis in A375S2 cells. Furtherly, this study was carried out to investigate what kind of cytokines plays an important role in this process. The results revealed that AIII induced apoptosis through activating c-Jun N-terminal protein kinase (JNK) or extracellular signal related kinase (ERK) signaling pathway and generating NO. However, JNK or ERK inhibited autophagy, while NO had no effect on autophagy. Therefore, JNK, ERK or NO regulates two programmed death processes in different ways. AIII did not show obvious cytotoxic effect on human peripheral blood mononuclear cells, which indicated that AIII has less side effects on normal cells, and could be considered as a leading compound for developing novel anticancer drug.

Glioblastoma multiform (GBM) is the most frequent and aggressive form of brain tumors in adults. However, the development of more efficient and safe nonviral vector gene therapy represents a promising therapeutic approach, using a tumor-specific killer gene, named apoptin. In this study, we describe the efficacy of non-viral gene delivery vectors, the amino acid-conjugated PAMAM derivatives (PAMAM-H-R and PAMAM-H-K) in delivering a therapeutic gene, displaying affinity toward human primary glioma cells (GBL-14 cells) and dermal fibroblasts. We analyzed transfection efficiency, using luciferase (Luci) and a pDNA encoding for enhanced fluorescent protein (EGFP), and cytotoxicity in both cells. The results show that transfection efficiency of PAMAM-H-R improved compared to native PAMAM dendrimer, but cytotoxicity of PAMAM-H-R and PAMAM-H-K were very low. We treated both cells with a polyplex formation of PAMAM-H-R or PAMAM-H-K/apoptin, and analyzed their cellular uptake and localization by flow cytometry and confocal microscopy. Furthermore, we analyzed the endosomal escape effect using TEM images, and found that PAMAM-H-R showed very fast escape from endosome to the cytosol. Caspase 3 activity assay, cell cycle distribution, and JC-1 analysis showed apoptosis induced by apoptin in GBL-14 cells. This indicates that PAMAM-H-R can be a potential nonviral vector gene delivery carrier for brain tumor therapy. The present study demonstrates that PAMAM-H-R/apoptin gene polyplex can be used as an effective therapeutic candidate for GBM due to its selective induction of apoptosis in primary glioma cells as a potential nonviral gene delivery carrier for brain tumor therapy., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Cisplatin [cis-diammine-dichloroplatinum (II)] is a widely used chemotherapeutic agent, and one of its most severe side effects is ototoxicity. In the course of developing a new protective agent against cisplatin-induced ototoxicity, we have been interested in a novel synthetic compound, 3-Amino-3-(4-fluoro-phenyl)-1H-quinoline-2,4-dione (KR-22335). We evaluated the effectiveness of KR-22335 as an otoprotective agent against cisplatin-induced toxicity. The otoprotective effect of KR-22335 against cisplatin was tested in vitro in cochlear organs of Corti-derived cell lines, HEI-OC1, and in vivo in a zebrafish (Danio rerio) model. Cisplatin-induced apoptosis, cell cycle arrest and an increase in intracellular reactive oxygen species (ROS) generation were demonstrated in HEI-OC1 cells. KR-22335 inhibited cisplatin-induced apoptosis and mitochondrial injury in HEI-OC1 cells. KR-22335 inhibited cisplatin-induced activation of JNK, p-38, caspase-3 and PARP in HEI-OC1 cells. Scanning and transmission electron micrographs showed that KR-22335 prevented cisplatin-induced destruction of kinocilium and stereocilia in zebrafish neuromasts. Tissue TUNEL of neuromasts in zebrafish demonstrated that KR-22335 blocked cisplatin-induced TUNEL positive hair cells in neuromasts. The results of this study suggest that KR-22335 may prevent ototoxicity caused by the administration of cisplatin through the inhibition of mitochondrial dysfunction and suppression of ROS generation. KR-22335 may be considered as a potential candidate for protective agents against cisplatin-induced ototoxicity., (Copyright © 2013 John Wiley & Sons, Ltd.)

Objective: To investigate the expression and relationship of programmed cell death 5 (PDCD5) and cell apoptosis in the parotid gland after leading duct ligation in rat and elucidate the role of PDCD5 on the atophy of parotid gland., Methods: The Wistar rat model of leading duct ligation was established, and the samples of parotid gland were obtained from different time point (0, 1, 3, 5, 7, 14, 21, 30, 60, 90 and 120 d). The expression of PDCD5 protein was examined by immunohistochemistry. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)., Results: The distribution of PDCD5 protein in normal parotid was in cytoplasm with uniformity. The expression of PDCD5 protein was significantly increased and reached the peak at 3 d (1.261 ± 0.048) following main duct ligation. PDCD5 was located both in cytoplasm and nuclear of parotid gland cells. The PDCD5 density in acinar cells was higher than that in duct cells at day 1 and 3 after duct ligation (P < 0.01). The apoptotic cells were obviously upregulated at 3 d after duct ligation. The apoptosis index observed in acinar cells [(21.750 ± 0.119)%] was more than that in duct cells [(5.720 ± 0.205)%]. The difference of apoptosis index between acinar cells and duct cells was statistically significant (P < 0.01). The increased PDCD5 levels were positively correlated with cell apoptosis induced by duct ligation., Conclusions: The expression of PDCD5 is associated with the atophy of the parotid gland after rat parotid duct ligation, indicating that PDCD5 might play an important role in apoptotic pathways after parotid duct ligation.

The aim of this study was to investigate the gene expression profiles of acute promyelocytic leukemia (APL) cell line NB4 treated with arsenic trioxide (As2O3) by using cDNA microarray. cDNA probes were prepared through reverse transcription from mRNA of NB4 cells treated with or without arsenic trioxide. The probes were labeled with Cy3 and Cy5 fluorescence dyes individually, hybridized with cDNA microarray representing 201 different human genes, and their fluorescent intensities were scanned. The genes were screened through the analysis of the difference in the gene expression profile. The results showed that after the treatment of arsenic trioxide (2 micromol/L), 6 genes were up-regulated, and 12 genes related to apoptosis and signal transduction were down-regulated. The p21, survivin, cdc2 and Wee1Hu genes may be related to the differentiation and/or apoptosis of NB4 cells induced by As2O3. It is concluded that p21, survivin, cdc2 and Wee1Hu may play an important role in the mechanism underling arsenic trioxide-mediated NB4 cell apoptosis.

Objective: To investigate the regulation of tissue factor (TF) on doxorubicin-induced apoptosis in human neuroblastoma., Method: The expression of TF was examined by Western blotting. TF siRNA-pSUPER plasmid was constructed by inserting a specific 19-nt silencing sequence targeting TF gene into pSUPER vector. Transfection of TF siRNA-pSUPER was performed using lipofectamine 2000. The activation of caspase-3 and PARP induced by doxorubicin was tested by Western blotting. The apoptotic cells were stained by Hochest 33342 and counted under fluorescence inverted microscope., Results: (1) Human neuroblastoma cell line SK-N-MC expressed high level of TF. (2) Downregulation of TF expression was achieved by transfection of TF siRNA-pSUPER into SK-N-MC cells in a dose-dependent manner. (3) Cleavage of caspase-3 and PARP was increased in transfected SK-N-MC cell with down-regulation of TF. (4) TF siRNA treatment at 1 microg/ml for 8 h significantly increased apoptotic cell number in transfected SK-N-MC cells compared to that in non-transfected cells (P < 0.05) while exposing to 1 microg/ml doxorubicin for 8 h., Conclusions: Downregulation of TF expression by specific siRNA vector could increase the cytotoxicity of doxorubicin and enhance doxorubicin-induced apoptosis in human neuroblastoma cells.

Objective: To investigate the effects of mangiferin on telomerase activity and apoptosis in K562 cells lines and study the melocular mechanism of it's antileukemic., Methods: Cell apoptosis was observed by light microscopy and transmission electron microscopy; The expression of Fas was measured by flow cytometry; Polymerase chain reaction enzyme linked immunoassay (PCR-ELISA) was used to assay telomerase activity of K562 cells., Results: Mangiferin could inhibit telomerase activity of K562 cells in a time-and-concentration-dependent manner. Meanwhile, it could induce apoptosis obviously and up-regulate the levels of Fas in K562 cells., Conclusion: Mangiferin can inhibit telomerase activity of K562 cells, and the mechanism of effect is maybe relate to inducing apoptosis and the expression of Fas protein.

Mammalian sterile 20-like kinase 1 (Mst1) is activated by both caspase-mediated cleavage and phosphorylation in response to apoptotic stimuli, including Fas ligation. Here, we examined the possible role of the tumor suppressor RASSF1A in Mst1 activation and Mst1-mediated apoptosis induced by death receptor signaling. Immunoprecipitation and immunofluorescence analyses revealed that Mst1 was associated with RASSF1A in cultured mammalian cells, with both proteins colocalizing to microtubules throughout the cell cycle. Whereas purified recombinant RASSF1A inhibited the kinase activity of purified recombinant Mst1 in vitro, overexpression of RASSF1A increased the kinase activity of Mst1 in intact cells, suggesting that regulation of Mst1 by RASSF1A in vivo involves more than the simple association of the two proteins. Both the activation of Mst1 and the incidence of apoptosis induced by Fas ligation were markedly reduced in cells depleted of RASSF1A by RNA interference and were increased by restoration of RASSF1A expression in RASSF1A-deficient cells. Moreover, the stimulatory effect of RASSF1A overexpression on Fas-induced apoptosis was inhibited by depletion of Mst1. These findings indicate that RASSF1A facilitates Mst1 activation and thereby promotes apoptosis induced by death receptor signaling.

This study was aimed to investigate the effects and the mechanism of mangiferin on chronic myeloid leukemia cell lines K562 cells in vitro. The antiproliferation effects of mangiferin on K562 leukemia cells were tested by tetrazolium salt (MTT) method; the apoptosis induced by mangiferin on K562 cell line was explored by means of cell morphology, DNA gel electrophoresis and flow cytometry. The changes in bcr/abl gene expression was detected by using reverse transcriptase (RT)-PCR. The results showed that five different concentrations of mangiferin (25 - 200 micromol/L) dose-dependently and time-dependently inhibited the proliferation of K562 cells, and induced apoptosis in K562 cell line. RT-PCR revealed that bcr/abl gene expression was down-regulated when K562 cells had been treated with different concentrations of mangiferin. In conclusion, mangiferin remarkably inhibits the proliferation of K562 leukemia cells in vitro, and induces apoptosis in K562 cell line probably through down-regulation of bcr/abl gene expression.

The multifunctional serine protease thrombin has been shown to be a specific agonist for a variety of functional responses of cells including osteoblasts. The current study was conducted to determine if thrombin was capable of inhibiting apoptosis in osteoblasts, and if so, to examine the mechanism by which this occurred. Thrombin (20-100 nM) significantly inhibited apoptosis in serum-starved cultures of the human osteoblast-like Saos-2 cell line and cultures of primary osteoblasts isolated from mouse calvariae, as well as dexamethasone-treated primary mouse osteoblasts. Inhibition of serum deprivation-induced apoptosis was shown to require thrombin's specific proteolytic activity. Primary mouse osteoblasts were found to express two functional thrombin receptors, PAR-1 and PAR-4. Thrombin inhibited serum deprivation-induced apoptosis in osteoblasts isolated from PAR-1 null mice to the same degree as in osteoblasts isolated from wild-type mice. Treatment of serum-deprived osteoblasts, isolated from either PAR-1 null or wild-type mice, with a PAR-4-activating peptide failed to significantly inhibit apoptosis compared to the relevant control. Medium conditioned by thrombin-treated osteoblasts, in which thrombin had been inactivated, was able to inhibit serum deprivation-induced osteoblast apoptosis almost as well as thrombin itself. Blocking protein synthesis, by cycloheximide pretreatment of the conditioning cells, prevented this action. The ability of known osteoblast survival factors, such as transforming growth factor beta1, fibroblast growth factor-2, insulin-like growth factor-II, and interleukin-6, to inhibit serum deprivation-induced osteoblast apoptosis was also tested. None of these factors was able to inhibit serum deprivation-induced osteoblast apoptosis to the same extent as thrombin. The results presented here demonstrate that thrombin treatment of osteoblasts inhibits apoptosis induced either by dexamethasone or by serum deprivation. Furthermore, it does so independently of the known thrombin receptors by bringing about the synthesis and/or secretion of an unknown survival factor or factors, which then act in an autocrine fashion to inhibit apoptosis.

The possibility of immunotherapy for lymphoma by single FasL-Fas way was investigated. After pBillneo-mFasL was transformed into competent E. coli DH5alpha and amplified, the plasmid DNA was prepared and purified from the DH5alpha. To determine the primary structure and inserting direction of mFasL cDNA gene in pBillneo-mFasL, the plasmid DNA was cleaved by restriction enzyme, and the mFasL cDNA of pBillneo-mFasL was amplified by polymerase chain reaction (PCR), the DNA sequence of the PCR product was analysed by automatic DNA sequencing. After pBillneo-mFasL was transfected into COS-7 cells by liposome, the COS-7 cells were selected with G418 selective medium, and the expressing levels of mFasL cDNA on the COS-7 cell membrane was assayed by Western Blot. After the COS-7 cells higher expressing mFasL protein and mouse lymphoma cell line Yac-1 expressing Fas were cocultured for 5 hours, the suspending Yac-1 cells were collected and labeled by annexin V/PI kit. The apoptosis rate of the Yac-1 cells was tested by flow cytometry. The EcoRI cleaving products of pBillneo-mF asL included 920 bp and 7227 bp fragments. Its Hind III cleaving products included 1293 bp and 6807 bp fragments. These results showed: (1) the length of DNA sequence containing mFasL cDNA within pBillneo-mFasL is the same as theoretical length; (2) the inserting of mFasL cDNA in pBillneo-mFasL was in positive orientation. The expected 890 bp DNA fragments of mFasL cDNA (from ATG to +36 bp following TAA) emerged in PCR product with pBillneo-mFasL as a template. The sequencing result of the PCR product equaled the known mFasL cDNA sequence in the gene bank. The COS-7 cells transfected by pBillneo-mFasL and selected with G418 culture medium expressed more mFasL membrane protein assayed by Western Blot. After the COS-7 cells were cocultured with Fas(+) Yac-1 cells in different E:T ratios (1:1, 5:1 and 10:1) for 5 hours, the apoptosis rates of Yac-1 cells were (22 +/- 4.8)%, (32.18 +/- 7.8)%, and (51.8 +/- 5.4)%, respectively. These were obviously different from the control group (P < 0.01), in which the COS-7 cell was transfected by pBillneo (not carrying mFasL gene). It was concluded that lymphoma cells highly expressing Fas can be effectively killed through single Fas-FasL way in vitro.