Article

Evaluation of effects of chitosan in preventing hemorrhagic cystitis in rats induced by cyclophosphamide

Department of Urology, Nagoya City University Medical School.
Hinyokika kiyo. Acta urologica Japonica 05/1995; 41(4):289-96.
Source: PubMed

ABSTRACT

Hemorrhagic cystitis is a common problem following cyclophosphamide or radiation therapy. Chitosan has been shown to be an effective hemostatic agent and promoter of wound healing in animal experiments. We evaluated the safety and efficacy of intravesical chitosan in an animal model of cyclophosphamide cystitis. Hemorrhagic cystitis was induced in female F344 rats by intraperitoneal cyclophosphamide, 100 mg/kg. Chitosan solution (0.3 ml) was instilled intravesically on day 1 (Group 1), on days 1, 3, and 5 (Group 2), or 1 hour after the administration of cyclophosphamide (Group 3). The rats in group 4 were treated with chitosan diluent on day 1 after cyclophosphamide, and the rats in group 5 received intravesical chitosan without cyclophosphamide. Sequential examination revealed decreased mortality and lower incidences of severe bladder bleeding, necrosis and inflammation in Group 3. Treatment delayed until after the appearance of the cystitis, especially repeated treatments, appeared to make the cyclophosphamide-induced changes worse. Used within 1 hour of cyclophosphamide administration, before the cystitis develops, chitosan seemed to have the possibility to inhibit the appearance of hemorrhagic cystitis. In addition to the changes in the bladder, severe changes occurred in the kidneys secondary to cyclophosphamide.

Download full-text

Full-text

Available from: Takehiko Okamura, Mar 25, 2014
  • [Show abstract] [Hide abstract]
    ABSTRACT: Carboxymethyl-chitin–glucan (CMCG) isolated from Aspergillus niger was ultrasonicated to decrease its molecular weight. Ultrasonicated CMCG with molecular weight 0.19×10−5 was administered either intraperitoneally or orally prior to cyclophosphamide (CP) injection and its effect on the frequency of micronuclei in polychromatic erythrocytes of mouse bone marrow was evaluated. Both ways of CMCG administration significantly decreased the clastogenic effect of CP. The protective effect of CMCG was concentration dependent, with a higher decrease achieved by 200 mg/kg than by 100 mg/kg b.wt. Ultrasonic depolymerization of high molecular CMCG resulted in its anticlastogenic effect against CP not only on intraperitoneal, but also on oral administration, achieved by decreasing its molecular weight. Ultrasonication proved to be an efficient way to obtain molecules of CMCG able to pass through the cell walls of the gastrointestinal tract.
    No preview · Article · Jan 1998 · Mutation Research/Genetic Toxicology and Environmental Mutagenesis
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Stents are largely used in surgical procedures to relieve pathological obstructions. The purpose of the present study was to design and prepare a biocompatible stent with a self-expandable mechanism. Thin films were prepared from deacetylated chitosan (4% w/v) dissolved in acetic acid solution (2% v/v). The chitosan films were tested by a calibrated tensiometer to measure the Young's module (E). The films were used to manufacture stents by pulling and winding them around a cylindrical rod in a helical fashion. Thirteen stents (diameter = 0.5 +/- 0.05 mm, length approximately 4 mm) were inserted into the vas deferens of wistar rats. Upon stent insertion, the vasal anastomosis was achieved with a laser-soldering technique. The animals were sacrificied 8 weeks later. The stress test showed that the chitosan film was elastic (maximum strain = 105% +/- 6%, E = 0.7655 +/- 0.0288 Mpa). The stents self-expanded by releasing their elastic energy. All the stents but one remained open inside the vasa despite high incidence of sperm granuloma. A biocompatible and self-expandable stent with a helical design is proposed.
    Full-text · Article · Aug 2001 · Biomaterials
  • Source

    Preview · Article · Sep 2001 · BJU International
Show more