Drug Discoveries & Therapeutics
Online ISSN : 1881-784X
Print ISSN : 1881-7831
ISSN-L : 1881-7831
Volume 5, Issue 3
Displaying 1-8 of 8 articles from this issue
Editorial
  • Xishan Hao
    2011 Volume 5 Issue 3 Pages 107-108
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Biotherapy became recognized as the fourth modality of cancer treatment applied after surgical treatment, radiotherapy and chemotherapy since the Biological Response Modifier (BRM) theory was proposed by Dr. Oldham in the 1980s (1). Cancer biotherapy is a therapeutic method that could prohibit the growth of tumors through mobilizing the host's immune system or via the effect of biological agents, thereby regulating the body's biological responses (2). Biotherapy is regarded as the most vigorous and promising strategy among the cancer multimodality treatments in this century due to its advantages of high safety and effectiveness as well as low side-effects (2-4). Treatment methods of biotherapy are emerging with the development of such subjects as immunology, cell biology and molecular biology. Currently, the main approaches of biotherapy include molecule targeted therapy, gene therapy and cell therapy. ...
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Review
  • Takako Yokozawa, Young A Lee, Eun Ju Cho, Kinzo Matsumoto, Chan Hum Pa ...
    2011 Volume 5 Issue 3 Pages 109-118
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Senescence-accelerated mouse prone/8 (SAMP8), a murine model of accelerated senescence, shows age-related deficits in learning and memory. The oral administration of oligomers improved spatial and object recognition impairment in SAMP8. The expression of phosphorylated neurofilament-H was significantly elevated in the hippocampal CA1. This indicates that oligomers induce an increase in the density of axons. To investigate the protective mechanisms of oligomers against brain dysfunction with aging, we carried out a receptor tyrosine kinase phosphorylation antibody array, and clarified that the administration of oligomers led to an increase in the phosphorylation of vascular endothelial growth factor receptor (VEGFR)-2, suggesting the neuroprotective role of oligomers. The phosphorylation of VEGFR-2 was more markedly increased in the hypothalamus and choroid plexus than in other brain regions of SAMP8. Memory in oligomer-treated mice was impaired by SU1498, a VEGFR-2-specific antagonist. Elucidating the relationship between memory impairment with aging and VEGFR-2 signaling may provide new suggestions for protection against memory deficit in the aging brain. In addition, we revealed that the administration of oligomers extended the life span of SAMP8. Oligomers elevated SIRT1 expression, which is recognized as an essential factor for life span extension in the brain. However, the administration of oligomers did not induce stereotypical behaviors such as rearing, jumping, or hanging from the lid of a cage, while food restriction increased these frequencies without a significant change in motor function. The present study suggests the promising role of oligomers as an anti-aging agent to extend life span.
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Brief Report
  • Bo Jiao, Yahui Zhang, Yanna Cheng, Jianjun Gao, Qingzhu Zhang
    2011 Volume 5 Issue 3 Pages 119-124
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Diabetic nephropathy is the most common and severe renal complication of diabetes mellitus. The present study sought to investigate the renoprotective effects of a combination therapy of valsartan and low molecular weight heparin (LMWH) in rats with diabetic nephropathy induced by uninephrectomy and streptozotocin. The animals were divided into five groups as follows: sham-operated rats, diabetic control rats, diabetic rats treated with 20 mg/kg/day valsartan, diabetic rats treated with 600 IU/kg/day LMWH, diabetic rats treated with a combination of valsartan and LMWH (valsartan 10 mg/kg/day and LMWH 300 IU/kg/day). The treatment regimen was maintained for 8 weeks. Treatment with valsartan, LMWH, or a combination of the two had no significant effect on blood glucose levels. However, the urine protein excretion levels signifi cantly decreased for the three drug treatment groups; the most dramatic decreases were observed in the combination treatment group. Kidney histology was examined using periodic acid-Schiff staining and immunohistochemical staining of extracellular matrix proteins. Results indicated that histopathology improved markedly in the three drug treatment groups; combination therapy had an equal or better effect than monotherapy in terms of decreasing the abnormal thickness of the glomerular basal membrane, the ratio of the area of the mesangial region with respect to the total area of renal glomeruli, and the accumulation of collagen IV and laminin in kidney tissue. In addition, serum levels of transforming growth factor-β1 (TGF-β1) also markedly decreased in the drug treatment groups according to ELISA. However, there were no significant differences between the combination therapy group and monotherapy group. These results suggest that a combination of valsartan and LMWH at half the dose used in monotherapy is better at improving glomerular permeability in rats with diabetic nephropathy.
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Original Articles
  • Katsutoshi Imamura, Kenichi Ishii, Hiroshi Hamamoto, Kazuhisa Sekimizu
    2011 Volume 5 Issue 3 Pages 125-129
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Sheep red blood cells (SRBCs) rapidly aggregated when injected into the blood (hemolymph) of living silkworms. SRBCs also rapidly aggregated when incubated with hemolymph in vitro. SRBCs did not aggregate when incubated with single hemolymph components, hemocytes and cell-free plasma separated by centrifugation, whereas incubation with the mixture of components induced SRBC aggregation, suggesting that both hemocytes and plasma are required for the reaction. Treatment of hemocytes with sodium azide inhibited SRBC aggregation. On the other hand, SRBCs pre-incubated with hemocytes aggregated in the plasma, even in the presence of sodium azide. SRBC aggregation was not observed when the SRBCs were physically separated from the hemocytes by a polycarbonate filter. These findings suggest that SRBCs are directly attacked by hemocytes and become sensitive to humoral factors that cause SRBC aggregation.
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  • Masanori Miyauchi, Masashi Murata, Keiko Shibuya, Erina Koga-Yamakawa, ...
    2011 Volume 5 Issue 3 Pages 130-135
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Arabino-mycolates are components of the cell-wall skeleton of Mycobacterium bovis BCG (BCG-CWS). It is known that synthesized arabino-mycolates induce the production of tumor necrosis factor alpha (TNF-α) in murine macrophage cell lines at an intensity similar to that of BCG-CWS. However the immunological activity of natural arabino-mycolates isolated from BCG has not been investigated, probably due to the complexity of the molecule. In this paper, we investigated the immunostimulatory activity of arabino-mycolates isolated from BCG-CWS by acid hydrolysis. Arabino-mycolates obtained by acid hydrolysis from the originally prepared CWS (SMP-105) of M. bovis BCG Tokyo 172 strain consisted mainly of mono-arabinose mono-mycolate, penta-arabinose tetra-mycolate and hexa-arabinose tetra-mycolate fractions. Arabino-mycolates significantly induced TNF-α production with an intensity comparable to that of CWS and enhanced delayed type hypersensitivity (DTH) reactions against inactivated tumor cells. Arabino-mycolates-induced TNF-α production was completely dependent on TLR2 and MyD88 pathways. These findings indicate that isolated natural arabino-mycolates possess potent adjuvant immunostimulatory activity.
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  • Lobna A. Kassem, Maha M. Gamal El-Din, Nadia A. Yassin
    2011 Volume 5 Issue 3 Pages 136-143
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Vincristine (VCR) is a potent anticancer drug, but neurotoxicity is one of its most important dose-limiting toxicities. In this study, we investigated the neurotoxic effect of VCR, the possible mechanisms and the role of erythropoietin (EPO) in the protection against VCR-induced neurotoxicity in a rat model. The neurotoxicity of VCR and protective effect of EPO were examined using the tail flick test and by recording electrophysiological characteristics in isolated sciatic nerve. To elucidate the underlying mechanisms, mRNA expression of N-methyl-D-aspartate (NMDA) receptor, an index of glutamate excitotoxicity, and calcitonin gene-related peptide (CGRP), an important regulator of vascular tone, were measured in both spinal cord and sciatic nerves using an RT-PCR method. After intraperitoneal injection at a dose of 150 μg/kg three times weekly for five consecutive weeks, VCR significantly decreased the latency of tail withdrawal reflex, the amplitude of maximum compound action potential (MCAP) and chronaxie, and prolonged the duration of action potential (AP) and relative refractory period (RRP), but it had no effect on conduction velocity. VCR increased NMDA receptor expression and decreased CGRP expression. Forty μg/kg of EPO improved all VCR-induced changes, except chronaxie, while a higher dose of 80 μg/kg reversed all parameters and its effect was more prominent on tail flick test latency and NMDA receptor expression. These results suggested that VCR might cause increased nerve excitability and induce a state of glutamate excitotoxicity through enhancing NMDA receptor expression and diminishing CGRP expression, thus resulting in axonal degeneration. EPO had an obvious neuroprotective effect probably through decreasing NMDA receptor expression and increasing CGRP expression both centrally and peripherally.
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  • Kiattisak Saeio, Wantida Chaiyana, Siriporn Okonogi
    2011 Volume 5 Issue 3 Pages 144-149
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    This work was undertaken to explore antityrosinase and antioxidant activities of twenty essential oils of edible Thai plants. Antityrosinase activity against mushroom tyrosinase was examined by means of the dopachrome method using L-dopa as an enzymatic substrate. The essential oil of Cymbopogon citratus had the highest level of antityrosinase activity, followed by that of Ocimum canum with enzymatic inhibition of 69 ± 4 and 66 ± 3%. GC-MS revealed that geranial and neral were the two most abundant components of their chemical compositions. Antioxidant activity was gauged by the free radical scavenging activity test and ferric reducing/antioxidant power assay. The essential oil of Ocimum sanctum had the highest level of antioxidant activity, followed by the essential oil of Ocimum gratissimum. These results led to the conclusions that the essential oils of edible Thai plants exhibit important biological activities and are a promising choice as natural active ingredients because of their antityrosinase and antioxidant activities.
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  • Mohamed Etman, Mohamed Amin, Aly H. Nada, Mohamed Shams-Eldin, Osama S ...
    2011 Volume 5 Issue 3 Pages 150-156
    Published: June 30, 2011
    Released on J-STAGE: February 15, 2015
    JOURNAL FREE ACCESS
    Myrrh has long been used for its circulatory, disinfectant, analgesic, antirheumatic, antidiabetic, and schistosomicidal properties. Myrrh essential oil (MEO) was extracted from the oleo-gum resin of Commiphora molmol and formulated into emulsions and suppositories to mask/avoid its bitter taste. Three oil-in-water emulsions (E1-E3) were formulated and taste was evaluated by 10 volunteers. Particle size distribution was measured and correlated with excipients and the method of preparation. Physical and chemical stability testing was carried out for the optimum formulation (E2). Seven suppository formulations were investigated (F1-F7). Suppocire AML (F1) and Suppocire CM (F2) were chosen as fatty bases, and polyethylene glycol (PEG) 1500 (F3), PEG 4000 (F4), and a PEG blend (50% PEG 6000 + 30% PEG 1500 + 20% PEG 400) (F5) were chosen as water-soluble bases. A blend of PEG 1500 and Suppocire CM was also used (F7). Camphor (5%) was added to PEG 1500 (F6). Disintegration time, release rate, DSC, fracture points, and weight uniformity were evaluated. The overall average bitterness for formulations E1, E2, and E3 was 6.44, 4.15, and 3.45, respectively. Suppositories containing Suppocire AML had the fastest disintegration time (1.5 min) with dissolution efficiency (DE) of 56.8%. F3 containing PEG 1500 had a fast disintegration time of 2.5 min and maximum DE of 93.5%. The PEG blend had satisfactory release: (DE = 90.9%). A mixed fatty and water-soluble base (F7) had a disintegration time of 5 min and low DE (33.4%). A stable MEO emulsion with acceptable taste was formulated to improve patient acceptance and compliance. F3 suppositories yielded satisfactory results, while formulations containing fat-soluble bases exhibited poor release.
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