Laser influence on hepatic regeneration: spectrophotometric, molecular biology and L-FABP evaluation after partial hepatectomy at 70% ratio

• Grant number: 18/08853-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2018
• End date: September 30, 2020
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Orlando de Castro e Silva Junior
• Grantee: Catarina Piolla Graf
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Hepatic regeneration restores the proportion between body and organ after viable hepatectomy. This feature makes it possible a 70- 80% hepatectomy with a 20- 30% remaining functional organ. That way, it's importante to keep a 30% hepatic mass, under risk of organ failure. Objectives: Analyze laser effect upon hepatic regeneration under different wavelengths after 0, 24, 48, 72 hours and 7 days using L-FABP (Liver Fatty Acid Binding Protein), spectrophotometry and mitochondrial activity as an evalutation method. Method: 15 animals will be divided in 3 groups of 5 animals each: one group is control, one group will have the liver exposed to laser at 660 nm, 30 mW potency and irradiation dose of 22,5 J/cm2, and one group will have the liver exposed to laser at 780 nm, 30 mW potency and irradiation dose of 22,5 J/cm2. Each group will be divided in 5 subgroups of 1 animal, and the liver regeneration parameters will be analyzed after different time lengths after laser exposure: 0 hours, 24 hours, 48 hours, 72 hours and 7 days, when the animals will be sacrificed. This Project will be analyzed by ethics committee of animal experimentation of FMRP USP. The statistical analysis for comparison between the groups for spectrophotometric data will be made with MannWhitney test with a 5% significancy. The software GraphPad Prism 4.0 (GraphPad Prism 4.0, Inc, San Diego, CA, EUA) will generate the graphics and calculate the statistical significancy. (AU)