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Hassan MG, Hawwa MT, Baraka DM, El-Shora HM, Hamed AA. Biogenic selenium nanoparticles and selenium/chitosan-Nanoconjugate biosynthesized by Streptomyces parvulus MAR4 with antimicrobial and anticancer potential. BMC Microbiol 2024; 24:21. [PMID: 38216871 PMCID: PMC10785380 DOI: 10.1186/s12866-023-03171-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 12/22/2023] [Indexed: 01/14/2024] Open
Abstract
BACKGROUND As antibiotics and chemotherapeutics are no longer as efficient as they once were, multidrug resistant (MDR) pathogens and cancer are presently considered as two of the most dangerous threats to human life. In this study, Selenium nanoparticles (SeNPs) biosynthesized by Streptomyces parvulus MAR4, nano-chitosan (NCh), and their nanoconjugate (Se/Ch-nanoconjugate) were suggested to be efficacious antimicrobial and anticancer agents. RESULTS SeNPs biosynthesized by Streptomyces parvulus MAR4 and NCh were successfully achieved and conjugated. The biosynthesized SeNPs were spherical with a mean diameter of 94.2 nm and high stability. Yet, Se/Ch-nanoconjugate was semispherical with a 74.9 nm mean diameter and much higher stability. The SeNPs, NCh, and Se/Ch-nanoconjugate showed significant antimicrobial activity against various microbial pathogens with strong inhibitory effect on their tested metabolic key enzymes [phosphoglucose isomerase (PGI), pyruvate dehydrogenase (PDH), glucose-6-phosphate dehydrogenase (G6PDH) and nitrate reductase (NR)]; Se/Ch-nanoconjugate was the most powerful agent. Furthermore, SeNPs revealed strong cytotoxicity against HepG2 (IC50 = 13.04 μg/ml) and moderate toxicity against Caki-1 (HTB-46) tumor cell lines (IC50 = 21.35 μg/ml) but low cytotoxicity against WI-38 normal cell line (IC50 = 85.69 μg/ml). Nevertheless, Se/Ch-nanoconjugate displayed substantial cytotoxicity against HepG2 and Caki-1 (HTB-46) with IC50 values of 11.82 and 7.83 μg/ml, respectively. Consequently, Se/Ch-nanoconjugate may be more easily absorbed by both tumor cell lines. However, it exhibited very low cytotoxicity on WI-38 with IC50 of 153.3 μg/ml. Therefore, Se/Ch-nanoconjugate presented the most anticancer activity. CONCLUSION The biosynthesized SeNPs and Se/Ch-nanoconjugate are convincingly recommended to be used in biomedical applications as versatile and potent antimicrobial and anticancer agents ensuring notable levels of biosafety, environmental compatibility, and efficacy.
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Affiliation(s)
- Mervat G Hassan
- Botany and Microbiology Department, Faculty of Science, Benha University, P. O. Box 13511, Banha, Qalyubia, Egypt
| | - Mariam T Hawwa
- Botany and Microbiology Department, Faculty of Science, Benha University, P. O. Box 13511, Banha, Qalyubia, Egypt
| | - Dina M Baraka
- Botany and Microbiology Department, Faculty of Science, Benha University, P. O. Box 13511, Banha, Qalyubia, Egypt
| | - Hamed M El-Shora
- Botany Department, Faculty of Science, Mansoura University, P. O. Box 35516, Mansoura, Dakahliaو, Egypt
| | - Ahmed A Hamed
- Microbial Chemistry Department, National Research Centre, 33 El-Buhouth Street, P. O. Box 12622, Giza, Dokki, Egypt.
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Wang Z, Zhang L, Wang X. Molecular toxicity and defense mechanisms induced by silver nanoparticles in Drosophila melanogaster. J Environ Sci (China) 2023; 125:616-629. [PMID: 36375944 DOI: 10.1016/j.jes.2021.12.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 06/16/2023]
Abstract
The widely use of silver nanoparticles (AgNPs) as antimicrobial agents gives rise to potential environmental risks. AgNPs exposure have been reported to cause toxicity in animals. Nevertheless, the known mechanisms of AgNPs toxicity are still limited. In this study, we systematically investigated the toxicity of AgNPs exposure using Drosophila melanogaster. We show here that AgNPs significantly decreased Drosophila fecundity, the third-instar larvae weight and rates of pupation and eclosion in a dose-dependent manner. AgNPs reduced fat body cell viability in MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays. AgNPs caused DNA damage in hemocytes and S2 cells. Interestingly, the mRNA levels of the entire metallothionein gene family were increased under AgNPs exposure as determined by RNA-seq analysis and validated by qRT-PCR, indicating that Drosophila responded to the metal toxicity of AgNPs by producing metallothioneins for detoxification. These findings provide a better understanding of the mechanisms of AgNPs toxicity and may provide clues to effect on other organisms, including humans.
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Affiliation(s)
- Zhidi Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, Beijing 100193, China
| | - Liying Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, Beijing 100193, China
| | - Xing Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, Beijing 100193, China.
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3
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Alhoshani NM, Al-Johani NS, Alkeraishan N, Alarifi S, Alkahtani S. Effect of lycopene as an adjuvant therapy with 5-florouracil in human colon cancer. Saudi J Biol Sci 2022; 29:103392. [PMID: 35957702 PMCID: PMC9358465 DOI: 10.1016/j.sjbs.2022.103392] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 06/18/2022] [Accepted: 07/20/2022] [Indexed: 11/17/2022] Open
Abstract
Colon cancer (CC) is among the most frequent human cancers. Although, there is improvement in diagnostic techniques and existing treatment possibilities. Still, there is an unmet need for a novel treatment regimen that will improve the patient's quality of life. Here, the role of lycopene as an adjuvant therapy with 5-fluorouracil (5-FU) was explored in Caco2 colon cancer cells. Cells were exposed to a dose (3 µg/ml) of 5-FU and three doses (60, 90, 120 µg/ml) of lycopene either alone or as a mixture with 5-FU. Cytotoxicity, genotoxicity, oxidative stress, gene expression, and apoptotic parameters were investigated in this study. Findings showed that 5-FU or lycopene alone induced a dose-dependent increase in cytotoxicity which was slightly reduced in lycopene mixtures. Apoptotic assays showed that 5-FU induced a significant level of apoptosis but not necrosis. However, a lycopene mixture with 5-FU enhanced 5-FU triggered apoptosis and promoted necrosis. The mixtures were also shown to suppress mitochondrial membrane potential while gene expression analyses showed the induction of Bax expression upon exposure to mix 90 exhibited the highest Bax to Bcl-2 ratio and caspase 3 and 9 gene expression. Furthermore, the mixture treatment also inhibited cell migration in the wound healing assay compared to 5-FU alone. In conclusion, lycopene was found to sensitize Caco 2 cell lines to 5-FU treatment by inducing the expression of apoptotic genes. This, coupled with lycopene suppression of cytotoxicity and cell migration, indicates lycopene may be a promising candidate for adjuvant therapy involving 5-FU in CC.
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Affiliation(s)
- Norah M. Alhoshani
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Norah S. Al-Johani
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Nora Alkeraishan
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Saud Alarifi
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Saad Alkahtani
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
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4
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Samimi MS, Mahboobian MM, Mohammadi M. Ocular toxicity assessment of nanoemulsion in-situ gel formulation of fluconazole. Hum Exp Toxicol 2021; 40:2039-2047. [PMID: 34036827 DOI: 10.1177/09603271211017314] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE Fluconazole is an effective anti-fungal drug. Due to the limitations of fluconazole, such as poor water solubility and consequently low ocular bioavailability, an optimized fluconazole nanoemulsion in-situ gel formulation (temperature-sensitive) was developed. METHODS AND MATERIALS To verify formulation's safety for ophthalmic use, preparation was tested for potential ocular toxicity using a cell viability assay on retinal cells. The hen's egg test-chorioallantoic membrane (HET-CAM), as a borderline test between in vivo and in vitro techniques, was chosen for investigating the irritation potential of the formulation. HET-CAM test was done by adding the formulation directly to the CAM surface and monitoring the vessels visually in terms of irritation reactions. Eye tolerance was determined using the modified Draize test. RESULTS Viability assay on retinal cells displayed that fluconazole nanoemulsion in-situ gel formulation was non-toxic and can be safely used in the eye at concentrations of 0.1% and 0.5%. HET-CAM and Draize tests revealed that optimized formulation of fluconazole did not result in any irritation and was considered non-irritant and well-tolerated for ocular use. CONCLUSION Regarding to the findings of the three mentioned methods, fluconazole nanoemulsion in-situ gel formulation is harmless and as a proper and safe alternative, can be considered for ocular delivery of fluconazole in the future.
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Affiliation(s)
- M S Samimi
- Department of Pharmacology and Toxicology, School of Pharmacy, 48430Hamadan University of Medical Sciences, Hamadan, Iran
| | - M M Mahboobian
- Department of Pharmaceutics, School of Pharmacy, 48430Hamadan University of Medical Sciences, Hamadan, Iran
| | - M Mohammadi
- Department of Pharmacology and Toxicology, School of Pharmacy, 48430Hamadan University of Medical Sciences, Hamadan, Iran
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5
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TPGS modified nanoliposomes as an effective ocular delivery system to treat glaucoma. Int J Pharm 2018; 553:21-28. [DOI: 10.1016/j.ijpharm.2018.10.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 10/08/2018] [Accepted: 10/10/2018] [Indexed: 12/20/2022]
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Qiu HY, Wang PF, Li Z, Ma JT, Wang XM, Yang YH, Zhu HL. Synthesis of dihydropyrazole sulphonamide derivatives that act as anti-cancer agents through COX-2 inhibition. Pharmacol Res 2015; 104:86-96. [PMID: 26723906 DOI: 10.1016/j.phrs.2015.12.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Revised: 12/20/2015] [Accepted: 12/20/2015] [Indexed: 12/13/2022]
Abstract
COX-2 has long been exploited in the treatment of inflammation and relief of pain; however, research increasingly suggests COX-2 inhibitors might possess potential benefits to thwart tumour processes. In the present study, we designed a series of novel COX-2 inhibitors based on analysis of known inhibitors combined with an in silico scaffold modification strategy. A docking simulation combined with a primary screen in vitro were performed to filter for the lead compound, which was then substituted, synthesized and evaluated by a variety of bioassays. Derivative 4d was identified as a potent COX-2 enzyme inhibitor and exerted an anticancer effect through COX-2 inhibition. Further investigation confirmed that 4d could induce A549 cell apoptosis and arrest the cell cycle at the G2/M phase. Moreover, treatment with 4d reduced A549 cell adhesive ability and COX-2 expression. The morphological variation of treated cells was also visualized by confocal microscopy. Overall, the biological profile of 4d suggests that this compound may be developed as a potential anticancer agent.
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Affiliation(s)
- Han-Yue Qiu
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China
| | - Peng-Fei Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China
| | - Zhen Li
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China
| | - Jun-Ting Ma
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China
| | - Xiao-Ming Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China.
| | - Yong-Hua Yang
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China.
| | - Hai-Liang Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210046, People's Republic of China.
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7
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Nakamura S, Xu F, Ninomiya K, Nakashima S, Oda Y, Morikawa T, Muraoka O, Yoshikawa M, Matsuda H. Chemical structures and hepatoprotective effects of constituents from Cassia auriculata leaves. Chem Pharm Bull (Tokyo) 2015; 62:1026-31. [PMID: 25273061 DOI: 10.1248/cpb.c14-00420] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An 80% aqueous acetone extract of Cassia auriculata leaves was found to show a protective effect on D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes. From the 80% aqueous acetone extract, we isolated a new benzocoumarin glycoside, avaraoside I (1), and a new flavanol dimer, avaraol I (2), together with 29 known constituents. The structures of the new compounds were elucidated on the basis of chemical and physicochemical evidence. In addition, three isolated compounds, pseudosemiglabrin (15, 0.0011%), (2S)-7,4'-dihydroxyflavan(4β→8)-catechin (22, 0.00075%), and (2S)-7,4'-dihydroxyflavan(4β→8)-gallocatechin (23, 0.092%), displayed hepatoprotective effects equivalent to that of the hepatoprotective agent, silybin.
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8
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Panda S, Bisht S, Malakar D, Mohanty AK, Kaushik JK. In vitro culture of functionally active buffalo hepatocytes isolated by using a simplified manual perfusion method. PLoS One 2015; 10:e0118841. [PMID: 25790478 PMCID: PMC4366187 DOI: 10.1371/journal.pone.0118841] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 01/09/2015] [Indexed: 01/27/2023] Open
Abstract
Background In farm animals, there is no suitable cell line available to understand liver-specific functions. This has limited our understanding of liver function and metabolism in farm animals. Culturing and maintenance of functionally active hepatocytes is difficult, since they survive no more than few days. Establishing primary culture of hepatocytes can help in studying cellular metabolism, drug toxicity, hepatocyte specific gene function and regulation. Here we provide a simple in vitro method for isolation and short-term culture of functionally active buffalo hepatocytes. Results Buffalo hepatocytes were isolated from caudate lobes by using manual enzymatic perfusion and mechanical disruption of liver tissue. Hepatocyte yield was (5.3±0.66)×107 cells per gram of liver tissue with a viability of 82.3±3.5%. Freshly isolated hepatocytes were spherical with well contrasted border. After 24 hours of seeding onto fibroblast feeder layer and different extracellular matrices like dry collagen, matrigel and sandwich collagen coated plates, hepatocytes formed confluent monolayer with frequent clusters. Cultured hepatocytes exhibited typical cuboidal and polygonal shape with restored cellular polarity. Cells expressed hepatocyte-specific marker genes or proteins like albumin, hepatocyte nuclear factor 4α, glucose-6-phosphatase, tyrosine aminotransferase, cytochromes, cytokeratin and α1-antitrypsin. Hepatocytes could be immunostained with anti-cytokeratins, anti-albumin and anti α1-antitrypsin antibodies. Abundant lipid droplets were detected in the cytosol of hepatocytes using oil red stain. In vitro cultured hepatocytes could be grown for five days and maintained for up to nine days on buffalo skin fibroblast feeder layer. Cultured hepatocytes were viable for functional studies. Conclusion We developed a convenient and cost effective technique for hepatocytes isolation for short-term culture that exhibited morphological and functional characteristics of active hepatocytes for studying gene expression, regulation, hepatic genomics and proteomics in farm animals.
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Affiliation(s)
- Santanu Panda
- Animal Biotechnology Centre, National Dairy Research Institute, Karnal, 132001, Haryana, India
| | - Sonu Bisht
- Animal Biotechnology Centre, National Dairy Research Institute, Karnal, 132001, Haryana, India
| | - Dhruba Malakar
- Animal Biotechnology Centre, National Dairy Research Institute, Karnal, 132001, Haryana, India
| | - Ashok K. Mohanty
- Animal Biotechnology Centre, National Dairy Research Institute, Karnal, 132001, Haryana, India
| | - Jai K. Kaushik
- Animal Biotechnology Centre, National Dairy Research Institute, Karnal, 132001, Haryana, India
- * E-mail:
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Li J, Yu Z, Wang Q, Li D, Jia B, Zhou Y, Ye Y, Shen S, Wang Y, Li S, Bai L, Kan Q. Hyperammonia induces specific liver injury through an intrinsic Ca2+-independent apoptosis pathway. BMC Gastroenterol 2014; 14:151. [PMID: 25145683 PMCID: PMC4236522 DOI: 10.1186/1471-230x-14-151] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 08/15/2014] [Indexed: 02/06/2023] Open
Abstract
Background Numerous pathological processes that affect liver function in patients with liver failure have been identified. Among them, hyperammonia is one of the most common phenomena.The purpose of this study was to determine whether hyperammonia could induced specific liver injury. Methods Hyperammonemic cells were established using NH4Cl. The cells were assessed by MTT, ELISA, and flow cytometric analyses. The expression levels of selected genes and proteins were confirmed by quantitative RT-PCR and western blot analyses. Results The effects of 20 mM NH4Cl pretreatment on the cell proliferation and apoptosis of primary hepatocytes and other cells were performed by MTT assays and flow cytometric analyses. Significant increasing in cytotoxicity and apoptosis were only observed in hepatocytes. The cell damage was reduced after adding BAPTA-AM but unchanged after adding EGTA. The expression levels of caspase-3, cytochrome C, calmodulin, and inducible nitric oxide synthase were increased and that of bcl-2 was reduced. The Na+-K+-ATPase activities in hyperammonia liver cells was no signiaficant difference compaired with the control group, but was decreased in astrocytes. NH4Cl pretreatment of primary hepatocytes promoted the activation of mitochondrial permeability transition pores and the mitochondria swelled irregularly. Conclusions Hyperammonia induces specific liver injury through an intrinsic Ca2+-independent apoptosis pathway.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Quancheng Kan
- Department of Gastroenterology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
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Liu Z, Lv YJ, Song YP, Li XH, Du YN, Wang CH, Hu LK. Lysosomal membrane protein TMEM192 deficiency triggers crosstalk between autophagy and apoptosis in HepG2 hepatoma cells. Oncol Rep 2012; 28:985-91. [PMID: 22736246 DOI: 10.3892/or.2012.1881] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 02/08/2012] [Indexed: 11/06/2022] Open
Abstract
As constituents of lysosomes, lysosomal membrane proteins play important roles in lysosome-related autophagy and apoptosis. In a recent proteomic study of lysosomal proteins, we identified transmembrane protein 192 (TMEM192) as a novel lysosomal membrane protein candidate. Using specific anti-TMEM192 antibody and lysosomal markers, the lysosomal localization of TMEM192 was determined by immunofluorescence. TMEM192 shows a wide expression pattern in mouse tissues. Interestingly, TMEM192 was found to be highly expressed in tumor cell lines, while it was not expressed or was detected at low levels in normal cell lines. By knockdown of TMEM192 expression using specific siRNAs, we found that TMEM192-deficient HepG2 hepatoma cells show growth inhibition and increased apoptosis. Autophagy was shown to be activated through detection of LC3II expression. Increased apoptosis was inhibited by blocking the expression of the key autophagy gene Atg7 in TMEM192-deficient HepG2 cells. The results suggest that TMEM192 is important for tumor cell growth and proliferation. TMEM192 deficiency can induce autophagy in tumor cells, and can further activate apoptosis by the mitochondrial pathway through autophagy. TMEM192 promotion of autophagy may be a new route for tumor therapy.
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Affiliation(s)
- Zhen Liu
- Department of Radiation Oncology, Qilu Hospital, and Department of Oncology, Shandong University School of Medicine, Shandong 250012, PR China
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Li F, Sun JY, Liu M, Lu WY, Wang JY, Shi JY. Sterically stable liposomes improve the therapeutic effect of hepatic stimulator substance on fulminant hepatic failure in rats. Biochem Pharmacol 2011; 82:556-65. [PMID: 21664898 DOI: 10.1016/j.bcp.2011.05.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 05/20/2011] [Accepted: 05/24/2011] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND AIMS Few drugs have been confirmed to be effective for fulminant hepatic failure (FHF). The purpose of this study was to prepare sterically stable liposomes (SSL) encapsulating hepatic stimulator substance (HSS) and determine their therapeutic effect on FHF. METHODS HSS were encapsulated into SSL (HSS-SSL). FHF was induced in rats by thioacetamide (TAA) injection (400mg/kg, three times with a 24-h interval). The agents, including HSS-SSL, SSL, HSS, and sodium chloride (NS), were each injected intravenously 2h after the second and the third TAA injection. RESULTS Freshly prepared HSS-SSL had a mean size of 93.59nm and the average encapsulation efficiency was 37.20%. HSS encapsulated in SSL showed a longer half life and more potent target to injured livers than free HSS. Twenty-four hours after the third TAA-injection, the survival rate of HSS-SSL-treated rats (80%) was significantly higher than that of rats treated with NS (20%), SSL (25%), or HSS (50%). Histopathologic examination showed that there was the least necrosis and inflammation in the livers of HSS-SSL-treated rats. The incidence of stage 3 or 4 hepatic encephalopathy in HSS-SSL-treated rats was significantly lower than that in rats treated with other agents. The serum pro-inflammatory cytokine levels and hepatic lipid peroxidation levels were both markedly reduced, while hepatocyte proliferative rate was markedly increased after HSS-SSL treatment. CONCLUSION Encapsulation by SSL markedly improved the therapeutic effect of HSS on FHF in rats. Encapsulation by SSL may be an effective approach to enhance the therapeutic potency of drugs for FHF.
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Affiliation(s)
- Feng Li
- Department of Gastroenterology, Zhongshan Hospital affiliated to Fudan University, 180 Fenglin Road, Shanghai, China
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12
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Nakamura S, Zhang Y, Matsuda H, Ninomiya K, Muraoka O, Yoshikawa M. Chemical Structures and Hepatoprotective Effects of Constituents from the Leaves of Salacia chinensis. Chem Pharm Bull (Tokyo) 2011; 59:1020-8. [PMID: 21804248 DOI: 10.1248/cpb.59.1020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | | | | | | | - Osamu Muraoka
- Pharmaceutical Research and Technology Institute, Kinki University
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Samarakoon SR, Thabrew I, Galhena PB, De Silva D, Tennekoon KH. A comparison of the cytotoxic potential of standardized aqueous and ethanolic extracts of a polyherbal mixture comprised of Nigella sativa (seeds), Hemidesmus indicus (roots) and Smilax glabra (rhizome). Pharmacognosy Res 2010; 2:335-42. [PMID: 21713135 PMCID: PMC3111691 DOI: 10.4103/0974-8490.75451] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2010] [Revised: 08/23/2010] [Accepted: 01/12/2011] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND A decoction (hot-water extract) comprised of Nigella sativa (seeds), Hemidesmus indicus (roots), and Smilax glabra (rhizome) has been reported to prevent chemically-induced hepatocarcinogenic changes in rats and to exert significant cytotoxic effects on human hepatoma (HepG2) cells. However, the decoction used in previous studies to determine cytotoxicity was not standardized. Further, during preparation of pharmaceuticals for clinical use, it is more convenient to use an ethanolic extract. Therefore this study was carried out to (a) develop standardized aqueous and ethanolic extracts of the plant mixture (N. sativa, H. indicus, and S. glabra) used in the preparation of the original decoction, and (b) compare the cytotoxic effects of these two extracts by evaluating cytotoxicity to the human hepatoma (HepG2) cell line. METHODS Aqueous and ethanolic extracts have been standardized by evaluating organoleptic characters, physicochemical properties, qualitative and quantitative analysis of chemical constituents, and analysis of High Performance Liquid Chromatography (HPLC) and Thin Layer Chromatography (TLC) profiles. Cytotoxic potentials of the above standardized extracts were compared by evaluating their effects on the survival and overall cell activity of HepG2 cells by use of the 3-(4, 5-dimethylthiazol-2yl) -2, 5 - biphenyl tetrazolium bromide (MTT) and Sulphorhodamine B (SRB) assays. RESULTS Results from MTT and SRB assays demonstrated that both extracts exerted strong dose-dependent in vitro cytotoxicity to HepG2 cells. The standardized aqueous extract showed a marginally (though significantly, P<0.05) higher cyotoxic potential than the ethanolic extract. Thymoquinone, an already known cytotoxic compound isolated from N. sativa seeds was only observed in the standardized ethanolic extract. Thus, compounds other than thymoquinone appear to mediate the cytotoxicity of the standardized aqueous extract of this poly-herbal preparation. CONCLUSION It may be concluded that results obtained in the present study could be used as a diagnostic tool for the correct identification of these aqueous or ethanolic extracts and would be useful for the preparation of a standardized pharmaceutical product that may be used in the future for clinical therapy of hepatocellular carcinoma.
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Affiliation(s)
- Sameera R. Samarakoon
- Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Cumarathunga Munidasa Mawatha, 90, Colombo 3, Sri Lanka
| | - Ira Thabrew
- Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Cumarathunga Munidasa Mawatha, 90, Colombo 3, Sri Lanka
| | - Prasanna B. Galhena
- Department of Biochemistry and Clinical Chemistry, Faculty of Medicine, University of Kelaniya, Talagoole Road, Ragama, Sri Lanka
| | - Dilip De Silva
- Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka
| | - Kamani H. Tennekoon
- Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Cumarathunga Munidasa Mawatha, 90, Colombo 3, Sri Lanka
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Kamiya M, Oyauchi K, Sato Y, Yokoyama T, Wang M, Aizawa T, Kumaki Y, Mizuguchi M, Imai K, Demura M, Suzuki K, Kawano K. Structure-activity relationship of a novel pentapeptide with cancer cell growth-inhibitory activity. J Pept Sci 2010; 16:242-8. [PMID: 20401925 DOI: 10.1002/psc.1225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We previously reported that yamamarin, a pentapeptide with an amidated C-terminus (DILRG-NH(2)) isolated from larvae of the silkmoth, and its palmitoylated analog (C16-DILRG-NH(2)) suppressed proliferation of rat hepatoma (liver cancer) cells. In this study, we investigated the structure-activity relationship of yamamarin by in vitro assay and spectroscopic methods (CD and NMR) for various analogs. The in vitro assay results demonstrated that the chemical structure of the C-terminal part (-RG-NH(2)) of yamamarin is essential for its activity. The CD and NMR results indicated that yamamarin and its analog adopt predominantly a random coil conformation. Moreover, a comparison of NMR spectra of DILRG-NH(2) and C16-DILRG-NH(2) revealed that the N-terminal palmitoyl group of C16-DILRG-NH(2) did not affect the conformation of the C-terminal part, which is essential for activity. Together, these results should assist in the design of more sophisticated anticancer drugs.
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Affiliation(s)
- Masakatsu Kamiya
- Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan
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15
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Nakamura S, Okazaki Y, Ninomiya K, Morikawa T, Matsuda H, Yoshikawa M. Medicinal flowers. XXIV. Chemical structures and hepatoprotective effects of constituents from flowers of Hedychium coronarium. Chem Pharm Bull (Tokyo) 2009; 56:1704-9. [PMID: 19043243 DOI: 10.1248/cpb.56.1704] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The 80% aqueous acetone extract from the flowers of Hedychium coronarium was found to show a protective effect on D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes. On the other hand, two new labdane-type diterpene glycosides, coronalactosides I (1) and II (2), and a new labdane-type trinorditerpene, coronadiene (3), were isolated together with 8 known compounds from the extracts, which were obtained with chloroform and 80% aqueous acetone from the flowers of H. coronarium. The structures of new constituents were elucidated on the basis of chemical and physicochemical evidence. In addition, the principal constituents, coronaririn C and 15-hydroxylabda-8(17),11,13-trien-16,15-olide, displayed hepatoprotective effects, which were stronger than that of the hepatoprotective agent, silybin.
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16
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Fujiwara Y, Mangetsu M, Yang P, Kofujita H, Suzuki K, Ohfune Y, Shinada T. A Quinone Isolated from the Nest of Vespa simillima and Its Growth-Inhibitory Effect on Rat Liver Cancer Cells. Biol Pharm Bull 2008; 31:722-5. [DOI: 10.1248/bpb.31.722] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | | | - Ping Yang
- Graduate School of Agriculture, Iwate University
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17
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Serrano T, Mitry RR, Terry C, Lehec SC, Dhawan A, Hughes RD. The effects of immunosuppressive agents on the function of human hepatocytes in vitro. Cell Transplant 2007; 15:777-83. [PMID: 17269448 DOI: 10.3727/000000006783981530] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Calcineurin inhibitors (tacrolimus) and steroids continue to be an important component of hepatocyte transplantation protocols, despite reports of hepatotoxicity and inhibitory effects of steroids on cell proliferation. The aim of the study was to investigate whether isolated human hepatocytes were more vulnerable to the toxicity of these agents and also to investigate their effects on hepatocyte VEGF secretion, a vascular permeability factor suggested to be involved in the cell engraftment process. Human hepatocytes were isolated from donor livers/segments rejected or unused for orthotopic liver transplantation using a collagenase perfusion technique. Hepatocytes were plated for cell function tests and to determine VEGF production. Tacrolimus (0-50 ng/ml) and methylprednisolone (0-500 ng/ml) were added to the culture media and cells incubated for 24 h. Cell metabolic activity was assessed using the MTT assay, cell number using the SRB assay, and cell attachment from hepatocyte total protein content and protein synthesis using [14C]leucine incorporation. VEGF in culture supernatants was measured by ELISA. Tacrolimus and methylprednisolone had no statistically significant inhibitory effects on metabolic activity or protein synthesis compared to controls at all concentrations of the agents tested when added after plating. There were also no significant effects on cell attachment when tacrolimus or methylprednisolone was added at the time of cell plating. There were no differences in the responses obtained when either fresh or cryopreserved hepatocytes were used. The amount of VEGF secreted by untreated hepatocytes was highly variable (0-1400 pg/10(6) cells/24 h). VEGF levels in the culture supernatant from hepatocytes isolated from < or = 20-year-old donors (687 +/- 59 pg/10(6) cells/24 h) was significantly greater than from older donors (61 +/- 7 pg/10(6) cells/24 h; p = 0.003). Tacrolimus and methylprednisolone did not significantly affect VEGF secretion by hepatocytes. Tacrolimus and methylprednisolone did not have detrimental effects on the metabolic function of human hepatocytes, cell attachment, or VEGF secretion after cell isolation.
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Affiliation(s)
- Trinidad Serrano
- King's College London School of Medicine at King's College Hospital, Institute of Liver Studies, London, UK
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18
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Thabrew MI, Mitry RR, Morsy MA, Hughes RD. Cytotoxic effects of a decoction of Nigella sativa, Hemidesmus indicus and Smilax glabra on human hepatoma HepG2 cells. Life Sci 2005; 77:1319-30. [PMID: 15916774 DOI: 10.1016/j.lfs.2005.01.022] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Accepted: 01/11/2005] [Indexed: 11/17/2022]
Abstract
A decoction of Nigella sativa seeds, Hemidesmus indicus root and Smilax glabra rhizome is used by traditional medical practitioners in Sri Lanka to treat cancer and has been shown to prevent chemically induced carcinogenesis in rats. The cytotoxicity of the decoction and the individual plant extracts were tested on the human hepatoma HepG2 cell line. The effects of 24 h incubation with different concentrations (0--50 mg/ml) of the extracts on HepG2 cells were determined. Results from MTT and SRB assays, and [(14)C]-leucine and [(3)H]-thymidine uptake demonstrated that the decoction had a strong dose-dependent cytotoxic activity. The greatest inhibitory effects were observed on DNA synthesis with both the decoction (91+/-S.E. 3.7% inhibition) and N. sativa plant extract (88+/-3.8%) even at low concentrations (5 mg/ml). The three individual plant extracts were cytotoxic in the order of potency N. sativa>H. indicus>S. glabra. Flow cytometric analysis using Annexin V and propidium iodide staining showed that after 24 h exposure to the decoction, cells were in the late stage of apoptosis and/or necrosis. Further experiments are worthwhile to determine the anticancer potential of this plant decoction and its components.
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Affiliation(s)
- M Ira Thabrew
- Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka
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19
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Mitry RR, Hughes RD, Bansal S, Lehec SC, Wendon JA, Dhawan A. Effects of Serum from Patients With Acute Liver Failure Due to Paracetamol Overdose on Human Hepatocytes In Vitro. Transplant Proc 2005; 37:2391-4. [PMID: 15964424 DOI: 10.1016/j.transproceed.2005.03.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2005] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Our goal was to investigate the effects of serum from patients with acute liver failure due to paracetamol (acetaminophen) overdose on the function of human hepatocytes in vitro. METHODS Freshly isolated human hepatocytes plated on collagen-coated culture plates were, incubated (24 hours 37 degrees C) in medium containing pooled human sera (0%-80%) obtained from normal individuals or from patients with acute liver failure due to paracetamol overdose. The effects of the sera on cell function were assessed using MTT, [14C]-leucine incorporation, and cytochrome P450 (CYP1A1/2) activity assays. RESULTS The overall cellular metabolic activity was significantly greater at all concentrations after exposure to acute liver failure serum compared to normal serum. There were no significant differences in the decreases produced by pooled acute liver failure and normal sera at concentrations up to 80% on the [14C]-leucine incorporation or CYP1A1/2 activity. CONCLUSION The overall cell function/activity of human hepatocytes was not impaired in vitro on exposure to serum from patients with acute liver failure due to paracetamol overdose.
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Affiliation(s)
- R R Mitry
- Institute of Liver Studies, King's College London, and King's College Hospital, Denmark Hill, London SE5 9RS, UK
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20
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Matsuda H, Morikawa T, Ninomiya K, Yoshikawa M. Hepatoprotective constituents from Zedoariae Rhizoma: absolute stereostructures of three new carabrane-type sesquiterpenes, curcumenolactones A, B, and C. Bioorg Med Chem 2001; 9:909-16. [PMID: 11354673 DOI: 10.1016/s0968-0896(00)00306-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
New carabrane-type sesquiterpene lactones, curcumenolactones A, B, and C, were isolated from the 80% aqueous acetone extract of Zedoariae Rhizoma (Zingiberaceae), together with 41 sesquiterpenes and two diarylheptanoids. The absolute stereostructures of curcumenolactones A, B, and C were determined on the basis of physicochemical evidence, which included nuclear Overhauser effect (NOE) and circular dichroic (CD) spectroscopic analyses. Curcumenone, a principal carabrane-type sesquiterpene from Zedoariae Rhizoma, was found to show potent protective effect on D-galactosamine/lipopolysaccharide-induced acute liver injury in mice. In addition, curcumenolactones A and B and the other constituents showed protective effect on D-galactosamine-induced cytotoxicity in primary cultured rat hepatocytes.
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Affiliation(s)
- H Matsuda
- Kyoto Pharmaceutical University, Japan
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21
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Maeda S, Lin KH, Inagaki H, Saito T. Staurosporine promotion of formation of continuous monolayers of primary rat hepatocytes by improving attachment and spreading. Biosci Biotechnol Biochem 2000; 64:1985-7. [PMID: 11055409 DOI: 10.1271/bbb.64.1985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Primary rat hepatocytes form discontinuous monolayers even at their maximum density. Here, we show that staurosporine promotes attachment and spreading of hepatocytes onto culture substrates, so that hepatocytes form a close, continuous monolayer. This treatment did not attenuate major hepatic functions. Therefore, this technique is promising for making seamless cell-sheet structures, which will be applicable for cell-polarity experiments or artificial liver construction.
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Affiliation(s)
- S Maeda
- Department of Chemistry, National Industrial Research Institute of Nagoya, Japan.
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22
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Puviani AC, Ottolenghi C, Tassinari B, Pazzi P, Morsiani E. An update on high-yield hepatocyte isolation methods and on the potential clinical use of isolated liver cells. Comp Biochem Physiol A Mol Integr Physiol 1998; 121:99-109. [PMID: 9883573 DOI: 10.1016/s1095-6433(98)10109-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Isolated hepatocytes are a suitable system for the study of hepatic physiology and metabolism. They are also used for pharmacological and toxicological studies related to hepatic uptake, metabolism, excretion and toxicity of xenobiotics, as well as morphological and metabolic effects induced in the liver as a result of drug or toxic substance exposure. In this paper, the enzymatic methods for hepatocyte isolation in some mammalian species are reviewed, and methods for evaluating cell purification and assessment of cellular morphology and function are also examined. More recently, interest in hepatocyte transplantation has increased, and the clinical experimentation of hepatocyte-based liver support systems has attracted the attention of scientists and hepatologists. From a clinical perspective, using isolated hepatocytes could be useful both for supporting an acutely devastated liver, a chronically diseased liver, and for correcting genetic disorders resulting in metabolically deficient states. Reports of clinical usage of isolated allogenic hepatocytes in hepatocellular transplantation and of xenogenic liver cells in constructing bio-artificial liver support systems are promising, and are renewing interest in the development of methods for isolation and purification of hepatocytes.
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Affiliation(s)
- A C Puviani
- Department of Biology, University of Ferrara, Italy
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23
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In vitro studies on non-genotoxic carcinogens: resistance to DNA synthesis inhibition in GST-P-positive hepatocytes isolated from enzyme-altered foci-bearing rats. Toxicol In Vitro 1998; 12:279-85. [PMID: 20654410 DOI: 10.1016/s0887-2333(97)00102-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/1997] [Indexed: 11/24/2022]
Abstract
Hepatocytes were isolated from enzyme-altered foci (EAF)-bearing rats. Carcinogen-induced effects on DNA synthesis were studied in primary cultures of isolated cells. The test substance was added at the start and at 24hr. At 48hr the cultures were stained with antibodies against glutathione S-transferase P (GST-P) and DNA synthesis was estimated by thymidine incorporation. It was found that four of nine carcinogens induced a clear selective inhibition of DNA synthesis in GST-P-negative cells. Two of the four inhibiting carcinogens induced p53 in GST-P-negative cells, but did not in GST-P-positive cells. Of four tested non-carcinogens, none induced a selective inhibition of DNA synthesis in GST-P-negative hepatocytes. These findings suggest that this model system is useful when characterizing liver carcinogens and their carcinogenic mechanisms.
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24
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Matsuda H, Ninomiya K, Morikawa T, Yoshikawa M. Inhibitory effect and action mechanism of sesquiterpenes from Zedoariae Rhizoma on D-galactosamine/lipopolysaccharide-induced liver injury. Bioorg Med Chem Lett 1998; 8:339-44. [PMID: 9871681 DOI: 10.1016/s0960-894x(98)00021-3] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Hepatoprotective sesquiterpenes were isolated from the aqueous acetone extract of Zedoariae Rhizoma, the rhizome of Curcuma zedoaria ROSCOE (Zingiberaceae). Principal sesquiterpenes, furanodiene, germacrone, curdione, neocurdione, curcumenol, isocurcumenol, aerugidiol, zedoarondiol, and curcumenone and curcumin were found to show potent protective effect on D-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced acute liver injury in mice. Plausible action mechanisms for their hepatoprotective activity were clarified on the basis of the inhibitory effect on D-GalN-induced cytotoxicity in primary cultured rat hepatocytes, LPS-induced NO production in cultured mouse peritoneal macrophages, and D-GalN/tumor necrosis factor-alpha (TNF-alpha)-induced liver injury in mice.
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Affiliation(s)
- H Matsuda
- Kyoto Pharmaceutical University, Japan
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25
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New hepatoprotective saponins, bupleurosides III, VI, IX, and XIII, from Chinese Bupleuri Radix: Structure-requirements for the cytoprotective activity in primary cultured rat hepatocytes. Bioorg Med Chem Lett 1997. [DOI: 10.1016/s0960-894x(97)00418-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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26
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Resistance against ethacrynic acid in glutathione transferase 7-7 (GST-P)-positive hepatocytes isolated from carcinogen-treated rats: the role of cytoskeletal changes and ATP depletion. Toxicol In Vitro 1995; 9:937-43. [PMID: 20650171 DOI: 10.1016/0887-2333(95)00051-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/1995] [Indexed: 01/24/2023]
Abstract
Ethacrynic acid (Ea) is a substrate for glutathione transferase 7-7 (GST-P) in rat. Toxic effects of Ea have been related to its metabolism and GSH depletion, but resistance conferred by GSTP1-1 (the human homologue) has also been reported. Hepatocytes from enzyme altered foci (EAF) express GST-P, and a model for selection of resistant EAF cells has been developed using Ea as a toxic agent. In the present study the effects of Ea in this model have been characterized. Hepatocytes from foci-bearing rats were isolated. Isolated cells were exposed to Ea for 1-4 hr in suspension. They were then allowed to attach to collagen-coated plates in a serum-containing medium. Preferentially GST-P-positive cells attached after Ea treatment, thus increasing the number of positive cells per attached cells (GST-P-%). Extracellular GSH, as well as alpha-tocopherol, did not influence the Ea effect. However, the effect of Ea was counteracted by inhibitors of glutathione transferase activity. Taxol, a microtubule stabilizing agent, also counteracted the effect of Ea on GST-P-%. 1,2-Dichloro-4-nitrobenzene (DCNB, 0.4 mM), which is a substrate for other glutathione transferase isoenzymes than GST-P, also increased the GST-P-%. However, the effect of DCNB was not inhibited by taxol. It was also found that Ea induced a drop in ATP levels, but this effect, as well as cell leakage, came later than the loss of attachment. The data suggest that the critical effect of Ea was cytoskeletal changes, and that GST-P conferred resistance by detoxification of Ea.
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