Drug Discoveries & Therapeutics
Online ISSN : 1881-784X
Print ISSN : 1881-7831
ISSN-L : 1881-7831
Volume 11, Issue 6
Displaying 1-10 of 10 articles from this issue
Original Articles
  • Akihiro Matsumoto, Kayoko Murakami, Chie Watanabe, Masahiro Murakami
    2017 Volume 11 Issue 6 Pages 293-299
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    The development of peptide therapeutics owing to the advances in biotechnology has overcome some unmet medical needs; however, the route of administration is still limited to injections. Systemic delivery of insulin via an enteral route remains a great challenge due to its instability and low mucosal permeability. In this study, we investigated the effect of drug condensation in a suppository on the efficacy of insulin after rectal administration. Suppositories with dimples are prepared by a mold method using a hard fat (Suppocire® AM). Insulin or fluorescein isothiocyanate-dextran (molecular weight: 3,000-5,000) (FD4) as a model of a hydrophilic macromolecule was loaded in the dimples, and sealed with other lipids with different melting points. The in vitro release test showed that the time to 50% drug release depends on the melting point of the lipid for sealing but not on the number of dimples. The suppositories with one-, or three-dimple containing insulin and caprylocaproyl macrogol-8 glyceride (Labrasol®) were administered to rats at 0.5 U/head. The reduction in plasma glucose level was more significant for the one-dimple-type suppository than for the three-dimple-type although the one-dimple-type suppository contained less amount of Labrasol by one-third compared to the three-dimple-type. These results suggest that condensation of an insulin dose in a limited surface area of a suppository improves systemic availability via the rectal route with a reduced amount of an absorption enhancer.

    Download PDF (664K)
  • Mok-Ryeon Ahn, Ji-Yeon Bae, Da-Hye Jeong, Hideaki Takahashi, Yoshihiro ...
    2017 Volume 11 Issue 6 Pages 300-306
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    15 K is 1,2, 3-triazolyl ester of ketorolac, an old pain-killer, that blocks PAK1 by its R-form and inhibits COX-2 by its S-form. Mainly due to a robust increase in cell-permeability, 15K is over 500 times more potent than ketorolac in both anti-cancer and anti-PAK1 activities in cell culture with IC50 around 24 nM. However, 15K has no anti-AKT activity. Angiogenesis requires at least the kinase PAK1, and perhaps the kinase AKT as well, and is essential for a robust growth of solid tumors. Thus, in this study, we examined the potential antiangiogenic activity of 15K both in ovo and cell culture, prior to its in vivo (xenograft) anti-cancer activity test. The IC50 of 15K against the embryonic angiogenesis in ovo in CAM (chorioallantoic membrane) assay is around 1 nmol/egg. Surprizingly, however, 15K failed to inhibit the tube formation of HUVECs (human umbilical vein endothelial cells) in cell culture even at high as 150 μM. In an attempt to solve this mystery, we tested both in ovo as well as HUVECs-based anti-angiogenic activity of a potent survivin-suppressor called YM155, which blocks PAK1, in addition to AKT. YM155 is slightly more potent than 15K in CAM assay with IC50 around 0.5 nmol/egg, and apparenty inhibits the tube formation of HUVECs with IC50 around 18 nM. According to a few previous findings with the direct PAK1-inhibitor frondoside A (FRA), the tube formation of HUVECs depends solely on PAK1. Thus, the failure of 15K to affect their tube formation is most likely due to their drug (15K)-resistance. Furthermore, unlike FRA, YM155 killed HUVECs with IC50 around 18 nM, clearly indicating that AKT is essential for survival of HUVECs, instead of their tube formation.

    Download PDF (2572K)
  • Pimpak Phumat, Sakornrat Khongkhunthian, Phenphichar Wanachantararak, ...
    2017 Volume 11 Issue 6 Pages 307-315
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    In the present study, antimicrobial activity of Piper betle crude ethanol extract against 4 strains of oral pathogens; Candida albicans DMST 8684, C. albicans DMST 5815, Streptococcus gordonii DMST 38731 and Streptococcus mutans DMST 18777 was compared with other medicinal plants. P. betle showed the strongest antimicrobial activity against all tested strains. Fractionated extracts of P. betle using hexane, ethyl acetate, and ethanol, respectively, were subjected to antimicrobial assay. The result revealed that the fractionated extract from ethyl acetate (F-EtOAc) possessed the strongest antimicrobial activity against all tested strains. Its inhibition zones against those pathogens were 23.00 ± 0.00, 24.33 ± 0.58, 12.50 ± 0.70 and 11.00 ± 0.00 mm, respectively and its minimum inhibitory concentrations were 0.50, 1.00, 0.50 and 1.00 mg/mL, respectively. Interestingly, the minimum concentration to completely kill those pathogens was the same for all strains and found to be 2.00 mg/mL. Killing kinetic study revealed that the activity of F-EtOAc was dose dependent. HPLC chromatograms of P. betle extracts were compared with its antimicrobial activity. An obvious peak at a retention time of 4.11 min was found to be a major component of F-EtOAc whereas it was a minor compound in the other extracts. This peak was considered to be an active compound of P. betle as it was consistent with the antimicrobial activity of F-EtOAc, the most potential extract against the tested pathogens. It is suggested that F-EtOAc is a promising extract of P. betle for inhibition of oral pathogens. Separation and structure elucidation of the active compound of this extract will be further investigated.

    Download PDF (788K)
  • Rinrampai Puttipan, Penpicha Wanachantararak, Sakornrat Khongkhunthian ...
    2017 Volume 11 Issue 6 Pages 316-322
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    The present study explores antimicrobial activities of Caesalpinia sappan extracts against three strains of oral pathogenic bacteria; Streptococcus mutans DMST9567 (Smu9), Streptococcus mutans DMST41283 (Smu4), and Streptococcus intermedius DMST42700 (Si). Ethanol crude extract of C. sappan (Cs-EtOH) was firstly compared to that of other medicinal plants using disc diffusion method. Cs-EtOH showed significantly higher effective inhibition against all tested strains than other extracts and 0.12% chlorhexidine with the inhibition zone of 17.5 ± 0.5, 18.5 ± 0.0, and 17.0 ± 0.0 mm against Smu9, Smu4, and Si, respectively. Three fractionated extracts of C. sappan using hexane, ethyl acetate, and ethanol, respectively, were further investigated. The fractionated extract from ethanol (F-EtOH) presented the strongest activities with the minimum bactericidal concentration (MBC) of 125-250 µg/mL. Killing kinetics of F-EtOH was depended on the bacterial species and the concentration of F-EtOH. Two-fold MBC of F-EtOH could kill all tested strains within 12 h whereas its 4-fold MBC showed killing effect against Si within 6 h. Separation of F-EtOH by column chromatography using chloroform/methanol mixture as an eluent yielded 11 fractions (F1-F11). The fingerprints of these fractions by high-performance liquid chromatography at 280 nm revealed that F-EtOH consisted of at least 5 compounds. F6 possessed the significantly highest antimicrobial activity among 11 fractions, however less than F-EtOH. It is considered that F-EtOH is the promising extract of C. sappan for inhibiting oral pathogenic bacteria and appropriate as natural antiseptic for further develop of oral hygiene products.

    Download PDF (594K)
  • Sakornrat Khongkhunthian, Chayarop Supanchart, Songwut Yotsawimonwat, ...
    2017 Volume 11 Issue 6 Pages 323-328
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    In vitro cytotoxicity of lidocaine hydrochloride (LH) and prilocaine hydrochloride (PH) to oral epithelial cells, isolated from tissue specimens of healthy volunteers, were evaluated. Cell vitality after treating with 1-20% anesthetic solutions for 5 and 30 min was investigated using F-actin and 4',6-diamidino-2-phenylindole staining technique and observed by fluorescence microscopy. Vitality rate of more than 90% was found in all anesthetic groups at both durations whereas no survived cell was found in a positive control group (sodium dodecyl sulfate). Lactate dehydrogenase (LDH) assay was performed to confirm the safety of both anesthetic solutions. Cell culture medium after treating with LH or PH for 5 and 30 min were collected and analyzed using commercial kits. The results showed no significant difference between the test groups and negative control group (untreated culture) with low LDH levels. In vivo inflammatory inducing effect of 5, 10, 20% LH or PH loaded rice gels was investigated in healthy volunteers. Tumor necrosis factor alpha (TNF-α) in gingival cervicular fluid was determined by ELISA technique. It was found that the expression of TNF-α was not different from the baseline. The expression of this inflammatory mediator caused by the commercial gel was higher than those of both anesthetic rice gels. It might be due to the effects of other excipients in the formulation of the commercial product. It is concluded that LH or PH possess no cytotoxicity to oral epithelium and the developed rice gel base and LH and PH rice gels do not induce inflammatory effect to oral tissues.

    Download PDF (1357K)
  • Heny Ekowati, Junko Arai, Ayu Sekarani Damana Putri, Firzan Nainu, Aki ...
    2017 Volume 11 Issue 6 Pages 329-335
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    Phytohemagglutinin (PHA) isolated from the family of Phaseolus vulgaris beans is a promising agent against viral infection; however, it has not yet been demonstrated in vivo. We herein investigated this issue using Drosophila as a host. Adult flies were fed lectin approximately 12 h before they were subjected to a systemic viral infection. After a fatal infection with Drosophila C virus, death was delayed and survival was longer in flies fed PHA-P, a mixture of L4, L3E1, and L2E2, than in control unfed flies. We then examined PHA-L4, anticipating subunit L as the active form, and confirmed the protective effects of this lectin at markedly lower concentrations than PHA-P. In both experiments, lectin feeding reduced the viral load prior to the onset of fly death. Furthermore, we found a dramatic increase in the levels of the mRNAs of phagocytosis receptors in flies after feeding with PHA-L4 while a change in the levels of the mRNAs of antimicrobial peptides was marginal. We concluded that P. vulgaris PHA protects Drosophila against viral infection by augmenting the level of host immunity.

    Download PDF (952K)
Brief Reports
  • Yutaro Motoi, Kazufumi Watanabe, Hiroyuki Honma, Yousuke Tadano, Hiros ...
    2017 Volume 11 Issue 6 Pages 336-341
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    CYP2D6 and SULT1A1 occasionally show copy number variations (CNVs), with a larger number generally indicating greater enzymic activity. However, those variations are difficult to calculate using standard methods. With digital PCR, a recently introduced method for CNV analysis, DNA molecules are subjected to limited dilution and separated into nano-scale droplets prior to a PCR assay. Absolute quantitation of copy number can then be performed with high accuracy and sensitivity by determining the number of droplets showing an amplified signal for the target gene. This is the first report of analyses of CYP2D6 and SULT1A1 CNVs using a digital PCR method with blood sample from Japanese subject. Primers and probes were synthesized for the target and reference genes, and copy number calculation was performed using a QX200 Droplet Digital PCR System. Our results showed that the copy numbers in CYP2D6*5 hetero, non-CNV, and CYP2D6xN subjects were 1, 2, and 3 to 4, respectively. In addition, in non-CNV and multiplication subjects, the number of copies for SULT1A1 was 2 and 3 to 6, respectively. We found that the present digital PCR method was useful as well as accurate. In the future, a combined genotyping, allele distinction, and copy number calculation technique will be helpful for analysis of enzymic activity.

    Download PDF (344K)
  • Soichiro Sawamura, Masatoshi Jinnin, Ikko Kajihara, Katsunari Makino, ...
    2017 Volume 11 Issue 6 Pages 342-345
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    These days various collagen supplements have widely been marketed. However, it has not been scientifically proved whether increasing collagen can actually prevent skin aging. Systemic sclerosis (SSc) is an autoimmune disease that is characterized by thickening of the skin caused by accumulation of collagen. In this study, we tried to evaluate facial skin characteristics and skin aging of SSc patients by using digital imaging system. As the result, the severity of wrinkles, texture and pores were significantly lower in SSc patients than control subjects. Among them, wrinkles showed better correlation with skin thickness score. Therefore, increased amount of collagen in scleroderma skin may directly affect wrinkles. In conclusion, attempt on collagen induction itself is reasonable and effective strategy in order to keep young appearance, although oral collagen supplementation may not directly reach to the skin.

    Download PDF (2313K)
Case Report
  • Takayuki Ishibashi, Masatoshi Jinnin, Ikko Kajihara, Satoshi Fukushima ...
    2017 Volume 11 Issue 6 Pages 346-348
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    A lot of diseases occur on the skin of elderly persons. We report four elderly cases of bullous dermatosis that did not meet various differential diagnoses. Japanese, heart failure, atrophic skin and leg edema probably due to aging, as well as flaccid or tense bullae localized in legs were the common factors to our patients. Such conditions may be increased in coming aging society. Accordingly, it is worth regarding such symptom as the new clinical entity, which may comfort patients with similar condition and attract further attention.

    Download PDF (806K)
  • Nitin Gupta, Arvind Kumar, Gagandeep Singh, Gogineni Ratnakar, Kutty S ...
    2017 Volume 11 Issue 6 Pages 349-352
    Published: December 31, 2017
    Released on J-STAGE: January 12, 2018
    JOURNAL FREE ACCESS

    Invasive fungal rhinosinusitis (FRS) is a potentially fatal illness requiring early diagnosis and aggressive treatment with surgery and antifungals. We report a case of chronic FRS in a recently diagnosed diabetic individual due to Curvularia lunata. Imaging revealed extension into the right orbit and right basifrontal lobe. This was further complicated by development of nosocomial mucormycosis which was attributed to voriconazole therapy. The patient responded well to debridement and amphotericin B based therapy. To our knowledge, there are no reported cases of invasive FRS due to Curvularia lunata. Also, breakthrough mucormycosis on voriconazole therapy is rarely seen in non-malignancy, non-transplant settings. The possibility of rare fungal infections (community and nosocomial) should be entertained in developing settings where fungal spores are ubiquitous.

    Download PDF (496K)
feedback
Top