Effects of strength training on lower limbs in obese rats with knee osteoarthritis

• Grant number: 17/10248-0
• Support Opportunities: Scholarships abroad - Research
• Start date: May 29, 2018
• End date: February 12, 2019
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Stela Márcia Mattiello
• Grantee: Stela Márcia Mattiello
• Host Investigator: Walter Herzog
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: University of Calgary, Canada
• Associated research grant: 13/00798-2 - The extracellular matrix in aging, exercise and in the tumor microenvironment, AP.TEM

Abstract

OBJECTIVE: The objective of this study is to evaluate the effects of strength training on lower limbs in obese rats with knee metabolic OA in lower limbs muscles and knee cartilage articular. METHODS: Thirty-six male, 10 to 12-week old Sprague Dawley rats will be housed individually and randomized into either a high-fat/high-sucrose diet-induced obesity group (DIO) or a lean age-matched control group (standard chow low fat diet group - LFD). Groups will be divided into 2 subgroups: 1) strength training and 2) sedentary. The high-fat and high-sucrose (HF) diet consists of 40% fat and 40% sucrose. The strength exercise will perform during 11 weeks in climbing sessions will performed 2 times per week with progressive weights secured to the animals' tails. Synovial fluid and serum will be collected as well as knee joints and left lower limb muscles. The joints will be processed and stained with Safranin-O fast green and analyzed under light microscopy, using the Modified Mankin score. Muscles will be frozen, processed and stained with Oil Red O (ORO) and presence of RAGE (receptor for advanced glycation end products) will be analyzed by immunohistochemical double-staining and presence of collagen using primary antibodies for Collagen I, III, IV. The cytokines IL-1², IL-6, IL-10, TNF-± and leptin in the serum and synovial fluid will be analyzed by the ELISA. DATA ANALYSIS: Data will be analyzed statistically in accordance with the distribution and variable category. Primary comparisons will be made across the experimental groups with the purpose of identifying if strength training had any effect on OA development of the knees of obese. (AU)