The anti-inflammatory effect of the low-intensity laser on hepatic fibrosis and cirrhosis induced by bile duct ligation

• Grant number: 18/09815-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2018
• End date: September 30, 2020
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Márcia Regina Nagaoka
• Grantee: Maria Eduarda Maehara
• Host Institution: Instituto de Saúde e Sociedade (ISS). Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil

Abstract

The low-level laser therapy has been extensively investigated as an anti-inflammatory and wound healing method. Previous studies have shown the effectiveness of low-level laser therapy in visceral organs, however little is known about its effect on the liver. Objectives: To investigate the therapeutic effects of low-level laser therapy in the liver fibrogenesis using an experimental model of bile duct ligation. Methods: Adult male Wistar rats (Rattus norvegicus) will be anesthetized and after laparotomy, the common bile duct will be located, isolated and doubly linked. The control group (Sham) will undergo the same procedure; however, it will not have their bile duct doubly connected. The laser therapy will be performed following application protocol with diferent time intervals. Inflammation will be evaluated by serum activity of aspartate- and alanine-aminotransferases. Hepatic fibrogenesis will be analyzed by morphometric analysis using the microscope AxioImager A2 (Zeiss, Germany) and the processor and image analyzer AxioVision version 4.8 (Zeiss, Germany). Furthermore, the measurement of metalloproteinases 2 and 9 will be performed by zymogram. Liver cell death and regeneration will be also evaluated by TUNEL and western blotting for Ki-68, respectively.