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Hiroshi Sakagami,
Shigeru Amano,
Toshikazu Yasui,
Kazue Satoh,
Seiji Shioda,
Taisei Kanamoto,
Shigemi Terakubo,
Hideki Nakashima,
Koichi Watanabe,
Tomoko Sugiura,
Madoka Kitajima,
Hiroshi Oizumi,
Takaaki Oizumi
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ABSTRACT: Previous studies have shown antiviral, antibacterial, and anti-inflammatory activity of alkaline extract of the leaves of Sasa senanensis Rehder (SE). In order to manufacture an SE-containing toothpaste for combating oral diseases, we investigated the possible interaction between the candidate ingredients of toothpaste: SE, isopropyl methylphenol (IPMP, antibacterial agent) and charcoal prepared from Sasa senanensis Rehder.
Cell viability of mock-infected, HIV-infected and UV-irradiated cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Superoxide radical scavenging activity was determined by electron-spin resonance spectroscopy. Antibacterial activity against Porphyromonas gingivalis 381 and Streptococcus mutans ATCC25175 was determined by the turbidity assay.
Exposure to less than 50% SE or less than 0.31 mM IPMP for 10 min scarcely damaged human cultured gingival and periodontal ligament fibroblasts. Both SE and IPMP showed bi-modal action, stimulating the bacterial growth at lower concentrations, but synergistically inhibiting it at higher concentrations. Addition of extremely high concentrations of charcoal enhanced both anti-HIV and anti-UV activity of SE.
Practically, addition of charcoal may not be recommendable, since one or two orders higher concentrations of charcoal as compared with SE, are required to achieve the synergistic effect for anti-HIV and anti-UV activity. Rather, addition of about one tenth of the amount of IPMP may be recommendable for enhancing the antibacterial activity.
In vivo (Athens, Greece) 03/2013; 27(2):275-84. · 1.17 Impact Factor
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ABSTRACT: We recently reported that eugenol exerted comparable cytotoxicity towards human normal and tumor cells. In the present study, we investigated the effect of eugenol on interleukin-8 (IL-8) production by IL-1β-stimulated oral cells.
The viable cell number was determined by direct cell counting with a hemocytometer after trypsinization. IL-8 released into the culture medium was determined by enzyme-linked immunosorbent assay (ELISA).
IL-1β (5 ng/ml) induced two orders of magnitude higher production of IL-8 by human cultured cells than unstimulated cells. Upon IL-1β stimulation, both gingival fibroblasts (HGF) and periodontal ligament fibroblasts (HPLF) produced the greatest amounts of IL-8 (approximately 200-300 ng/ml), followed by pulp cells (HPCs) (approximately 40-50 ng/ml), whereas skin keratinocyte (HaCat) and oral squamous cell carcinoma cells (HSC-2, HSC-4) produced much less IL-8 (less than 15 ng/ml). The production of IL-8 depended on growth factor(s), since the omission of fetal bovine serum from the culture medium resulted in an approximately 90% decline of IL-8 production. Eugenol (5-500 μM) significantly stimulated IL-8 production in HGF cells, but had bi-modal effects on HPCs, causing slight stimulation at lower concentration (5 μM) and a significant inhibition at higher concentration (500 μM), regardless of the presence or absence of serum. Eugenol exerted similar effects on lipopolysaccharide-stimulated HGFs and HPCs.
These results demonstrate that an anti-inflammatory effect of eugenol is observed in HPCs, but not in HGFs. The narrow therapeutic range of eugenol suggests the importance of careful usage of this compound for dental treatment.
In vivo (Athens, Greece) 03/2013; 27(2):269-73. · 1.17 Impact Factor
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ABSTRACT: We have recently reported that eugenol exerted indiscriminate cytotoxicity towards normal oral cells and oral squamous cell carcinoma (OSCC) cell lines without induction of apoptosis markers. In order to investigate the underlying mechanisms of cytotoxicity induction, we investigated the effect of short-term treatment with eugenol on the metabolic profiles of a human OSCC cell line (HSC-2).
The viable cell number was determined by direct cell counting with a hemocytometer after trypsinization. After washing with 5% D-mannitol solution (found to retain the highest amounts of intracellular metabolites among several washing conditions), cellular metabolites were extracted with methanol with internal markers and then subjected to metabolomic analysis.
Cytotoxic concentrations of eugenol induced the reduction of ATP utilization (assessed by a significant reduction of the AMP/ATP and ADP/ATP ratio), of oxidative stress (assessed by the increase in oxidized form of glutathione, cysteine-glutathione disulfide and methionine sulfoxide), and an increase in the polyamines and glycolytic metabolites.
The metabolic changes observed in this study suggest the induction of non-apoptotic cell death by eugenol.
In vivo (Athens, Greece) 03/2013; 27(2):233-43. · 1.17 Impact Factor
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ABSTRACT: We recently reported that the ethyl acetate (EtOAc)-soluble fraction of the methanol extract of the root of Rhinacanthus nasutus showed tumor-specific non-apoptotic cytotoxicity and antiosteoclastogenic activity. In the present study, we investigated whether five rhinacanthins, mostly isolated from the EtOAc-soluble fraction of this plant, are responsible for these activities.
The cytotoxic activity was determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) method. The 50% cytotoxic concentration (CC(50)) was determined by the dose-response curve. Tumor specificity (TS) was determined by the ratio of the mean CC(50) for normal cells to that of tumor cell lines. DNA fragmentation was assayed by agarose gel electrophoresis. Caspase-3 activation was monitored by substrate cleavage assay. Osteoclastogenesis was monitored by tartrate-resistant acid phosphatase (TRAP) activity in receptor activator of NF-κB ligand (RANKL)-stimulated bone marrow-derived macrophages.
Among five rhinacanthins (rhinacanthin C, G, N and Q, and rhinacanthone), rhinacanthin C exhibited the highest tumor specificity (TS=15.2). Rhinacanthin C did not induce internucleosomal DNA fragmentation nor caspase-3 activation, suggesting non-apoptotic cell death. Rhinacanthin C most potently inhibited the RANKL-stimulated osteoclastogenesis.
The present study suggests that rhinacanthin C may be responsible for the biological activity of the EtOAc-soluble fraction prepared from the methanolic extract of R. nasutus we previously reported on.
Anticancer research 02/2013; 33(2):453-9. · 1.73 Impact Factor
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ABSTRACT: We recently reported that an alkaline extract of the leaves of Sasa senanensis Rehder (SE) and Lentinus edodes mycelia extract (LEM), exhibiting lignin-carbohydrate complex (LCC)-like activity, protected cells from UV-induced injury (referred to as anti-UV activity). We investigated whether LCC is the major active components responsible for anti-UV activity.
Human oral squamous cell carcinoma HSC-2 cells were exposed to short UV irradiation in phosphate-buffered saline, containing different concentrations of LCC. After culturing for 48 h in fresh culture medium, the viable cell number was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. From the dose-response curve, the 50% cytotoxic concentration (CC(50)) and the concentration that increased the viability of the UV-irradiated cells to 50% of the control value (EC(50)) were determined. The selectivity index (SI) was determined by the following equation: SI=CC(50)/EC(50).
LCCs (Fr. VI) of pine cones and seed shell, and sulfated LCC exhibited relatively high anti-UV activity (SI=7.1-38), compared with that of SE and LEM. LCCs with lower lignin content (Fr. VII) exhibited anti-UV activity, approximately one half that of Fr. VI. However, polysaccharides (laminarin, pullulan, dextran) introduced with dimethylaminoethyl- or sulfate groups with different substitution ratios were totally inactive (SI<1). The introduction of a sulfate group to LCC did not enhance the anti-UV activity of LCC. Sodium ascorbate and vanillin were the most active (SI=65), whereas gallic acid (SI=5), epigallocatechin gallate (SI=2.6), ar-trumeron (SI<1), and turmeric extract (SI<1) were much less active.
The prominent anti-UV activity of SE and LEM seems to be generated by LCCs present in the extract.
In vivo (Athens, Greece) 01/2013; 27(1):133-9. · 1.17 Impact Factor
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ABSTRACT: Previous studies have shown antiviral, antibacterial and anti-inflammatory activity of alkaline extract of the leaves of Sasa senanensis Rehder (SE). However, active components have not been identified. We isolated the substances that exhibit anti-UV activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity from SE and estimated their putative structures.
The anti-UV substances (SEE-1 and SEE-2) were isolated from SE by ethanolic extraction, Wakosil chromatography and recycled high-performance liquid chromatography (HPLC) at a yield of 0.22 and 0.18%, respectively. The structural analysis was carried out with (1)H-nuclear magnetic resonance (NMR), (13)C-NMR and UV absorption.
SEE-1 exhibited approximately four-fold higher anti-UV activity and slightly lower DPPH radical-scavenging activity, compared to SE. SEE-1 was identified as p-coumaric acid derivative(s), a lignin precursor.
The present study demonstrated for the first time the presence of lignin precursors in SE, which may explain why SE exhibits many of the properties of lignin-carbohydrate complexes.
In vivo (Athens, Greece) 01/2013; 27(1):77-83. · 1.17 Impact Factor
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ABSTRACT: Aim: The cytotoxicity of four dental compounds, hydroquinone, benzoquinone, eugenol and phtharal towards human oral squamous cell carcinoma (OSCC) cell lines, normal human oral cells (gingival fibroblast, pulp cell, periodontal ligament fibroblast) and skin keratinocytes was investigated.
Viable cell number was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) method. The concentration that reduced the viable cells by 50% (CC(50)) and the concentration that increased the viability of UV-irradiated cells to 50% (EC(50)) were determined from the dose-response curves. The tumor-specificity index (TS) was determined by the ratio of the mean CC(50) for normal cells to the one for tumor cells. Apoptosis induction was monitored by assay of internucleosomal DNA fragmentation and caspase-3/-7 activation.
When both oral OSCC and normal oral cells were incubated for 4 h with any of hydroquinone, benzoquinone, eugenol and phtharal, irreversible cell growth inhibition, accompanied by cell death occurred without induction of apoptotic markers, although caspase-3/-7 activation was observed at 6 h or later. These compounds exhibited very low tumor-specificity (TS=0.4-1.3), as compared with anticancer drugs (5-fluorouracil, melphalan, peplomycin) (TS=4.1-9.7). Human skin keratinocytes were the most resistant to these drugs, and a long incubation time was required to induce irreversible growth inhibition. However, all dental compounds exhibited very low tumor-specificity (TS=0.4-2.4), compared to human skin keratinocytes and OSCC cell lines. None of the dental compounds exhibited any hormetic growth stimulation, nor protected the cells from UV-induced damage.
These results suggest that apoptosis is not involved in the early stage of growth inhibition induced by dental compounds.
In vivo (Athens, Greece) 01/2013; 27(1):85-95. · 1.17 Impact Factor
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ABSTRACT: We have previously reported that azulene-related compounds can protect cells from UV-induced cytotoxicity. However, due to their high water insolubility, their anti-UV activity could not be accurately determined. In the present study, we newly-synthesized a total of nine derivatives with higher water solubility, and re-investigated their anti-UV activity.
Cytotoxicity of these compounds against three human normal oral and three human oral cells squamous cell carcinoma cell lines (OSCCs) was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The concentration that reduced the viable cell number by 50% (CC(50)) and the concentration that increased the viability of UV-irradiated cells to 50% (EC(50)) were determined by the dose-response curves. Anti-UV activity (SI) was determined by the ratio of CC(50) to EC(50). The tumor specificity was determined by the ratio of the mean CC(50) value for the normal cells to that for OSCC cells. Apoptosis induction was evaluated by DNA fragmentation and caspase activation.
All compounds except one (sodium 7-isopropyl-3-ethylazulene-1-sulfonate) were new compounds, and showed some tumor specificity (TS value=1.4 to 3.5), without induction of hormesis or apoptosis at lower and higher concentrations, respectively. Sodium 3-methylazulene-1-sulfonate showed the highest tumor specificity and potent anti-UV activity, approximately one half that of sodium ascorbate, the positive control.
These data suggest the possible applicability of newly-synthesized water-soluble azulenes as skin care products protecting from UV irradiation.
In vivo (Athens, Greece) 01/2013; 27(1):119-26. · 1.17 Impact Factor
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ABSTRACT: Despite frequent use of topoisomerase inhibitors (TIs) as antitumor agents, their application to oral squamous cell carcinoma (OSCC) has not been reported. We investigated three inhibitors of topoisomerase I [camptothecin, irinotecan, SN-38 (active metabolite of irinotecan)] and two inhibitors of topoisomerase II (etoposide, teniposide) for their cytotoxicity towards a total of 15 human tumor cell lines and normal cultured cells. All TIs exhibited higher cytotoxicity towards tumor cell lines (OSCC, glioblastoma, myelogenous leukemia) as compared with normal mesenchymal (gingival fibroblast, pulp cell, periodontal ligament fibroblast) and epithelial cells (skin keratinocytes). Among TIs, SN-38 had the highest cytotoxicity towards OSCC cell lines, with a tumor specificity index of 1321 compared to mesenchymal cells and 22 compared with epithelial cells. SN-38 induced different types of cell death in two OSCC cell lines: apoptosis (caspase-3 activation and internucleosomal DNA fragmentation) in HSC-2 cells and autophagy (formation of autophagosome and secondary lysosome) in HSC-4 cells. The cell death of HSC-2 and HSC-4 cells was significantly inhibited by pre-treatment with caspase inhibitor (Z-VAD-FMK) and autophagy inhibitors (3-methyladenine, bafilomycin A1), respectively. The present study demonstrated that SN-38 is highly cytotoxic to OSCC cell lines, regardless of the type of induced cell death, suggesting its future application for chemotherapy of OSCC.
Anticancer research 11/2012; 32(11):4823-32. · 1.73 Impact Factor
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ABSTRACT: Intravenous anesthetics have been used during the treatment of various malignant tumors, however, their effects on oral tissues is not well-understood. In the present study, the cytotoxicity of five intravenous anesthetics towards oral tumor and normal cells was compared.
Tumor specificity index was determined by the ratio of the mean 50% cytotoxic concentration for normal cells to that for tumor cells. Apoptosis induction was monitored by internucleosomal DNA fragmentation and caspase-3, -8, and -9 activation. Fine cell structure was observed under transmission electron microscopy.
Benzodiazepines (midazolam and diazepam) exhibited higher cytotoxicity than barbiturates (thiopental and thiamylal), whereas propofol had the intermediate range of cytotoxicity. Midazolam showed the highest cytotoxicity. HL-60 cells were the most sensitive to midazolam, followed by epidermal keratinocytes, oral squamous cell carcinoma (OSCC), glioblastoma and then oral normal cells. Midazolam did not induce the production of apoptosis markers such as internucleosomal DNA fragmentation and activation of caspase-3, -8 and -9, but did induce the appearance of many vacuoles, mitochondrial swelling and cell membrane rupture in OSCC cell lines (HSC-2 and HSC-4) cells. The cytotoxicity of midazolam was not reduced by pre-treatment with autophagy inhibitors (3-methyladenine and bafilomycin A1).
These results suggest that midazolam may induce necrotic cell death, rather than apoptosis or autophagy, in OSCC cell lines.
Anticancer research 11/2012; 32(11):4737-47. · 1.73 Impact Factor
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ABSTRACT: In the current study, we isolated four known compounds, two phenanthrenes, 2,5-dihydroxy-4,9-dimethoxy phenanthrene [1] and 4-methoxyphenanthrene-2,7-diol (flavanthrinin) [2], one phenanthrenequinone, 5-hydroxy-2,3-dimethoxy-1,4-phenanthrenequinone [3], and one flavone, 3,5,7-trihydroxyflavone (galangin) [4], from the ethyl acetate (EtOAc) extract of Odontoglossum Harvengtense 'Tutu' through bioassay-guided fractionation, and investigated their biological activities.
The isolated compounds were identified with spectroscopic analysis and through comparison to literature values. Cytotoxic activity towards human tumor and normal cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Nitric oxide (NO) was determined by the Griess method. Radical scavenging activity was determined by electron spin resonance (ESR) spectroscopy. Osteoclastogenesis was monitored by tartrate-resistant acid phosphatase (TRAP) activity.
The compounds had slightly higher cytotoxicity towards human oral squamous cell carcinoma and leukemia cell lines as compared with human normal oral cells, yielding a tumor specificity value of 1.1-2.7. Among these four compounds, 1 most potently inhibited the lipopolysaccharide (LPS)-stimulated NO production and the receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis by mouse macrophage-like RAW264.7 cells. Micromolar concentrations of 1 scavenged the NO radical produced from 1-hydroxy-2-oxo-3-(N-3-methyl-3-aminopropyl)-3-methyl-1-triazene.
The present study demonstrated, for the first time, that 1 inhibited both macrophage activation and osteoclast differentiation, suggesting its possible anti-inflammatory action.
In vivo (Athens, Greece) 11/2012; 26(6):993-9. · 1.17 Impact Factor
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Shoji Tanaka,
Hitoshi Taga,
Kiyoshi Maehara,
Azusa Kaneshima,
Mamoru Machino,
Hiromi Onuma,
Miku Kaneko, Hiroshi Sakagami,
Masahiro Sugimoto,
Tomoyoshi Soga,
Masaru Tomita
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ABSTRACT: Occlusal raising method (so-called 'Template therapy') has been reported to alleviate various diseases and symptoms, but the underlying mechanism is not clear. We searched the low-molecular weight metabolite(s) in the saliva, the concentration of which is significantly changed by the template therapy.
One female patient with headache underwent the template therapy for 12 days, and her total saliva was subjected to non-targeted analysis using capillary electrophoresis time-of-flight mass spectrometry (CE-TOF-MS).
One hundred and thirteen substances were identified in the saliva. Glycine was the most abundant amino acid in the saliva, followed by alanine, serine and proline. After the start of the template therapy, her headache was alleviated, accompanied by a significant (p=0.042) increase of salivary concentration of glycine, as compared with total amino acids whereas that of other amino acids was not significantly changed. In the metabolomics profile, salivary concentration of large number of metabolites as compared with total metabolite concentration decreased, including N-acetylneuraminate (p=0.025) and p-hydroxyphenylacetate (p=0.039).
This pilot study demonstrated, to our knowledge for the first time, that only glycine exhibited unique changes among total metabolites, suggesting its significant role in template therapy.
In vivo (Athens, Greece) 11/2012; 26(6):1015-20. · 1.17 Impact Factor
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Tomohiko Matsuta, Hiroshi Sakagami,
Shoji Tanaka,
Mamoru Machino,
Mineko Tomomura,
Akito Tomomura,
Toshikazu Yasui,
Kazuyoshi Itoh,
Tomoko Sugiura,
Madoka Kitajima,
Hiroshi Oizumi,
Takaaki Oizumi
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ABSTRACT: Previous studies have shown antiviral, antibacterial, and anti-inflammatory activity of alkaline extract of the leaves of Sasa senanensis Rehder (SE). Here, we investigated whether SE is effective on oral lichenoid dysplasia and osteoclastogenesis.
A male patient with white lacy streaks in the oral mucosa was orally administered SE three times a day for 11 months. The area of white streaks was monitored by intraoral photography. Interleukin-6 and -8 in the saliva were determined by enzyme-linked immunosorbent assay. Osteoclastogenesis of mouse macrophage-like RAW264.7 cells, induced by receptor activator of nuclear factor-κB ligand (RANKL) was monitored by tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cell formation.
Long-term treatment with SE progressively reduced both the area of white steaks and the levels of salivary interleukin-6 and -8. SE significantly inhibited the macrophage differentiation towards osteoclasts.
The present study suggests the therapeutic potential of SE towards oral diseases.
In vivo (Athens, Greece) 11/2012; 26(6):957-62. · 1.17 Impact Factor
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Takao Kato,
Norio Horie,
Tomohiko Matsuta,
Umemura Naoki,
Tetsuo Shimoyama,
Tadayoshi Kaneko,
Taisei Kanamoto,
Shigemi Terakubo,
Hideki Nakashima,
Kaoru Kusama, Hiroshi Sakagami
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ABSTRACT: Aim: In order to search for new biological activities of Kampo medicines and their constituent plant extracts, we investigated whether they protect the cells from the cytotoxicity induced by UV irradiation and human immunodeficiency virus (HIV) infection.
Anti-UV/HIV activity (SI value) was evaluated as the ratio of the CC(50) (concentration that reduced the viable cell number by 50%) to the EC(50) (the concentration that increased the viability of UV-irradiated or HIV-infected cells to 50%): SI=CC(50)/EC(50). The content of glycyrrhizin in each sample was determined by high performance liquid chromatography (HPLC). Caspase-3/-7 activity was assayed by cleavage of poly ADP ribose polymerase using western blot analysis.
Among 25 plant extracts, Gardenia fruit had the highest anti-UV activity (SI≥8.0), followed by Glycyrrhiza (SI=4.3), Coptis rhizoma (SI=1.5), Cimicifuga rhizoma (SI>1.4), Saposhnikovia root (SI>1.3) and Japanese Gentian (SI>1.1). Among ten Kampo medicines, Unseiin and Hangesyashinto (SI>4.9) had the highest anti-UV activity, followed by Shosaikoto (SI>4.3), Saireito (SI>3.4), Rikkosan (SI>1.2) and Kikyoto (SI=1.1). Glycyrrhiza inhibited UV-induced caspase-3/-7 activation. Only Polyporus sclerotium (SI>4.4), Gardenia fruit (SI>2.7), Atractylodes lancea rhizoma (SI>1.9), Cnidium rhizoma (SI>1.5) and Japanese Angelica root (SI>1.1) exhibited some anti-HIV activity. There was no apparent correlation of their anti-UV/HIV activity and content of glycyrrhizin, a major component of Glycyrrhiza, which exhibited much higher anti-UV activity (SI=20.6) and some anti-HIV activity (SI>2.0).
The present study suggests the involvement of substances other than glycyrrhizin in the anti-UV/HIV activity of Kampo medicines and their constituent plant extracts.
In vivo (Athens, Greece) 11/2012; 26(6):1007-13. · 1.17 Impact Factor
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ABSTRACT: Two series of 1-(3-aminomethyl-4-hydroxyphenyl)-3-pyridinyl-2-propen-1-ones, designed as novel cytotoxins, were synthesized. The compounds had low CC(50) values in the micromolar range against HL-60 promyelocytic leukemic cells and HSC-2, HSC-3 and HSC-4 oral squamous cell carcinomas. The CC(50) values of these compounds were higher towards non-malignant HGF (gingival fibroblasts), HPC (pulp cells), and HPLF (periodontal ligament fibroblasts) cells, which reveals the tumour-selectivity of these enones. A representative compound 4c caused cleavage of PARP1 in HSC-2 cells but not in HGF cells, which may be a contributing factor to the tumour-selectivity.
Journal of Enzyme Inhibition and Medicinal Chemistry 07/2012; · 1.62 Impact Factor
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ABSTRACT: Local anesthetics are often administered to tumors and surrounding tissues during the surgery of the head and neck area, however their effects on oral tissues is not well understood. In the present study, the cytotoxicity of a total of seven local anesthetics towards oral tumor and normal cells was compared.
Tumor-specificity index was determined by the ratio of the mean 50% cytotoxic concentration against normal cells to that for tumor cells. Apoptosis induction was monitored by internucleosomal DNA fragmentation and caspase-3, -8, and - 9 activation. Fine cell structure was observed under transmission electron microscopy.
All local anesthetics showed slightly higher cytotoxicity towards oral squamous cell carcinoma (OSCC) cell lines than towards normal oral cells. Dibucaine, with a log p-value of approximately 3, was the most cytotoxic, followed by tetracaine, bupivacaine or ethylaminobenzoate, whereas lidocaine, procaine and mepivacain were much less cytotoxic. When the tumor-specificity was evaluated between OSCC and human skin keratinocytes, the index was 6.6. Dibucaine did not induce apoptosis of OSCC cells. On the other hand, dibucaine did induce mitochondrial injury and swelling, formation of secondary lysosomes, and at high concentrations, rupture of the cell membrane. Autophagy inhibitors did not reduce the cytotoxicity of dibucaine.
Necrosis may be involved in the induction of antitumor activity by dibucaine.
Anticancer research 07/2012; 32(7):2925-33. · 1.73 Impact Factor
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Takashi Yamazaki,
Masahiko Kobayashi,
Kumi Hirano,
Hiroyuki Onuki,
Jun Shimada,
Atsushi Yamazaki,
Yasushi Hibino,
Hiroshi Nakajima,
Yoshiko Yokote,
Shinji Takemoto,
Yutaka Oda, Hiroshi Sakagami
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ABSTRACT: We previously reported that contact with copper (Cu) induced immediate cell death via an oxidation-involved mechanism, and the Cu-induced oxidation and cell death were effectively alleviated under hypoxic conditions. In order to explore alternative strategies for the protection from the Cu-induced cytotoxicity, we investigated whether the inclusion of gold (Au) in the Cu plate, as alloy,has a protective effect.
Human gingival fibroblast (HGF) cells, established from periodontal tissues, were inoculated on Au/Cu alloy of different Au ratios. After incubation at 37°C for different times under normoxic conditions, cellular viability and amino acid consumption were determined. Changes in the elemental composition of the alloy and in the culture medium were chemically analyzed by X-ray photoelectron spectroscopy and by inductively coupled plasma-optical emission spectrometry.
Contact with the Cu plate induced cytotoxicity and cystine oxidation in time-dependent manners. Inclusion of Au at more than 10% in the alloy, completely abrogated the cytotoxicity and reduced the oxidation of Cu and the elution of Cu from the alloy.
Inclusion of Au as a component of alloy reduces the cytotoxicity of the Cu plate, possibly by reducing its oxidation.
In vivo (Athens, Greece) 07/2012; 26(4):651-6. · 1.17 Impact Factor
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Alejandro Mena Acra, Hiroshi Sakagami,
Tomohiko Matsuta,
Kazunori Adachi,
Sumiko Otsuki,
Hiroshi Nakajima,
Teho Koh,
Mamoru Machino,
Takashi Ogihara,
Koji Watanabe,
Shigeru Watanabe,
Angel Visoso Salgado,
Norma M Montiel Bastida
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ABSTRACT: Comparative study of the growth inhibition by different types of fluoride compounds used in dentistry has been limited. We investigated the effects of sodium fluoride (NaF), diammine silver fluoride [Ag(NH3)2F] and 5-fluorouracil (5-FU) on the growth of eleven human normal and tumor cells in total.
Viable cell number was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis induction was evaluated by caspase-3 activation and DNA fragmentation. Fluoride was determined using a fluoride-specific electrode.
All compounds had little or no growth stimulating effect (hormesis) on all cells. Ag(NH3)2F exhibited the highest cytotoxicity towards both normal and tumor cells. 5-FU had the selective cytostatic activity towards oral squamous cell carcinoma cell lines, whereas NaF was selectively cytotoxic towards glioblastoma cell lines. None of the compounds induced internucleosomal DNA fragmentation and only 5-FU induced slight activation of caspase-3 in an oral squamous cell carcinoma cell line (HSC-2). Cytotoxicity of fluoride compounds was not reduced by superoxide dismutase and catalase, reducing the possibility of the involvement of reactive oxygen species in the mechanism of action. Approximately 0.01-0.09% initially added NaF was recovered from the cells, whereas the cellular uptake of Ag(NH3)2F and 5-FU was below the detection limit.
Cytotoxicity of fluoride compounds may not be directly linked to their tumor specificity nor to their apoptosis-inducing activity.
In vivo (Athens, Greece) 07/2012; 26(4):657-64. · 1.17 Impact Factor
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Hiroshi Sakagami,
Tomohiko Matsuta,
Kazue Satoh,
Sumiko Ohtsuki,
Chiyako Shimada,
Taisei Kanamoto,
Shigemi Terakubo,
Hideki Nakashima,
Yurika Morita,
Atsuko Ohkubo,
Tadashi Tsuda,
Katsuyoshi Sunaga,
Jun Maki,
Tomoko Sugiura,
Madoka Kitajima,
Hiroshi Oizumi,
Takaaki Oizumi
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ABSTRACT: We have previously reported that alkaline extract of Sasa senanensis leaves (SE) showed potent anti-HIV, anti-UV and radical scavenging activity. In the present study, we investigated the biological activities of SE-10, a granulated powder of SE supplemented with lactose, lactitol, trehalose and tea extract.
Cell viability of mock-infected, HIV-infected, and UV-irradiated cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Scavenging activity of superoxide anion and hydroxyl radicals was determined by electron-spin resonance spectroscopy. Cytochrome P-450 (CYP)3A4 activity was measured by β-hydroxylation of testosterone in human recombinant CYP3A4.
SE-10 had slightly higher anti-HIV and anti-UV activities, but slightly lower radical-scavenging and CYP3A4-inhibitory activities, as compared with SE.
The present study demonstrates that the biological activities of SE were well preserved during the manufacturing process of SE-10.
In vivo (Athens, Greece) 05/2012; 26(3):411-8. · 1.17 Impact Factor
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Györgyi Horváth,
Péter Molnár,
Erika Radó-Turcsi,
József Deli,
Masami Kawase,
Kazue Satoh,
Toru Tanaka,
Satoru Tani, Hiroshi Sakagami,
Nóra Gyémánt,
József Molnár
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ABSTRACT: The aim of the present study was to compare carotenoid extracts of Rose hips (Rosa canina L.) with regard to their phytochemical profiles and their in vitro anti-Helicobacter pylori (H. pylori), cytotoxic, multidrug resistance (MDR) reversal and radical scavenging activity. Carotenoid composition was investigated in the different fractionation of rose hips, using extraction methods. Six main carotenoids - epimers of neochrome, lutein, zeaxanthin, rubixanthin, lycopene, β,β-carotene - were identified from Rose hips by their chromatographic behavior and UV-visible spectra, which is in accordance with other studies on carotenoids in this plant material. The active principles in the carotenoid extract might differ, depending upon the extraction procedures.
Acta biochimica Polonica 03/2012; 59(1):129-32. · 1.49 Impact Factor
