Effects of low infrared laser intensity in muscle repair in diabetic rats

• Grant number: 14/19565-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2014
• End date: December 31, 2016
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Ana Claudia Muniz Renno
• Grantee: Camila Manis de Almeida
• Host Institution: Instituto de Saúde e Sociedade (ISS). Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil

Abstract

Diabetes mellitus (DM) is a chronic metabolic disease linked to problems with muscle regeneration. Among the therapeutic approaches designed to promote muscle regeneration, laser therapy of low intensity (LLLT) has been considered a safe and effective clinical modality, however, the signaling pathways triggered by this action remain uncertain. The objective of this study is to evaluate the effects of LLLT on inflammatory and regenerative response after cryoinjury of the tibialis anterior (TA) in diabetic rats. Twenty-four Wistar rats will be divided into three groups (n = 8): (GC) control group - TA muscle criolesado without treatment; (GCD) diabetic animals with untreated TA muscle criolesado; (LIR) diabetic animals with TA muscle criolesado submitted to laser irradiation. The induction model of diabetes is streptozotocin (STZ) intra-venous. The damaged regions will get in touch location and irradiation for seven consecutive days starting immediately after induction treatment of crilesão using a GaAlAs laser (continuous, » = 808 nm, P = 30 mW; beam area = 0.028 cm2; t = 47 s, D = 50 J/cm2, E = 1.4 J; irradiance = 1.07 mW/cm2). The animals will be euthanized on the seventh day after injury for the withdrawal of the right TA muscle. Histochemical techniques will be performed to determine the morphology and morphometry of the injured and undergoing treatment with LLLT muscles. Furthermore, immunohistochemical analyzes will be performed to evaluate the molecular markers (COX-2, iNOS, MyoD, Myogenin) involved in the process of muscle regeneration. The results of this project will bring significant contribution to the understanding of mechanisms of action triggered by LLLT during the process of muscle regeneration in diabetic mice, therefore optimizing its use in the rehabilitation of musculoskeletal disorders. (AU)