Clinical, biochemical and histological study of the effect of antimicrobial photodynamic therapy on oral mucositis induced by 5-fluorouracil in hamsters

Photodiagnosis Photodyn Ther. 2015 Jun;12(2):298-309. doi: 10.1016/j.pdpdt.2014.12.007. Epub 2015 Jan 19.

Abstract

Oral mucositis (OM) is a debilitating side effect of chemotherapy, which can be relieved by phototherapy. Antimicrobial photodynamic therapy (aPDT) may be used for the treatment of OM, when infection is present. However, there are no studies showing that aPDT affects tissue repair process when used in the treatment of lesions caused by OM. This work aims to evaluate the effect of aPDT in healing OM induced by 5-Fluorouracil (5-FU). Two hundred forty-five hamsters were divided into two groups, control (C) and experimental, which were subdivided into 4 subgroups (Ch, ChP, ChL, aPDT). C group received only the vehicle of chemotherapy and anesthesia, whereas all animals of the experimental groups received anesthesia and chemotherapy agent 5-FU to induce OM. Ch group received no OM treatment; ChP group received an application of methylene blue (MB) 0.01%; ChL received irradiation with low-power-laser (LPL-660 nm/120 J /cm(2)/40 mW/4.4 J per point); and aPDT received MB and LPL irradiation. OM Clinical severity were daily assessed by a blinded examiner. The animals were sacrificed after 5, 7 and 10 days of experiment and their oral mucosa were removed for biochemical (enzymatic activity of SOD and catalase) and histological analyzes (light microscopy). After statistical analysis was performed, results showed that aPDT reduced the severity of OM on the tenth day of the experiment, when compared to the initial OM score (p < 0.05), as well as increased keratinization with organized collagen deposition in the lamina propria. In conclusion, aPDT can be safely used in animals with infected OM because it does not affect lesion-repairing processes.

Keywords: 5-Fluorouracil; Antimicrobial photodynamic therapy; Antioxidant system; Chemotherapy; Oral mucositis.

MeSH terms

  • Animals
  • Anti-Infective Agents / pharmacology
  • Anti-Infective Agents / therapeutic use*
  • Antineoplastic Agents / adverse effects
  • Cricetinae
  • Female
  • Fluorouracil / adverse effects
  • Low-Level Light Therapy
  • Methylene Blue / pharmacology
  • Methylene Blue / therapeutic use*
  • Photochemotherapy / methods*
  • Photosensitizing Agents / pharmacology
  • Photosensitizing Agents / therapeutic use*
  • Severity of Illness Index
  • Stomatitis / chemically induced
  • Stomatitis / drug therapy*

Substances

  • Anti-Infective Agents
  • Antineoplastic Agents
  • Photosensitizing Agents
  • Methylene Blue
  • Fluorouracil