Optical therapy associated with adipose tissue-derived stem cells for healing induced Tendinopathy in rats

• Grant number: 23/01276-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: November 01, 2023
• End date: April 30, 2027
• Field of knowledge: Biological Sciences - Biophysics - Radiology and Photobiology
• Principal Investigator: Martha Simões Ribeiro
• Grantee: Bruno Luis Raposo
• Host Institution: Instituto de Pesquisas Energéticas e Nucleares (IPEN). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Tendon (TD) ruptures may occur at the tendon-muscle junction, tendon-bone junction, orthe midpoint of the tendon portion. The incidence of injury is increased with athleticism,excessive use of the tendon related to occupational activities, and chronic degenerative diseases,such as tendinopathies accompanied by other rheumatic diseases from aging. Totalreconstruction of the tendon occurs through a surgical procedure. After surgery, in most cases,the tendons do not regenerate, and there is scar formation and necrosis, which are factors forthe functional disability of the patients. In the present study, mesenchymal stem cells derivedfrom human adipose tissue (H-ADSCs) and low-power LED (LBP) will be associated tostimulate differentiation into tenocytes and accelerate the healing of induced tendon injuries. Inthe first step, we will verify the effect of LBP (» = 660 ± 11 nm, irradiance of 40 mW/cm2), andH-ADSC differentiation in tenocytes in vitro. We will also develop H-ADSC spheroidspreconditioned with LBP. Subsequently, we will apply LBP to injured and treated tendons withcells differentiated into tenocytes and spheroids of H-ADSCs. For this, we will use adult maleWistar rats provided by the Ipen vivarium. The animals will be submitted to the surgicaltechnique for rupture and reconstruction of the Achilles tendon, with the following therapeuticapproaches per group: GC: control without treatment - spontaneous healing; GL: control withLBP only; GTD: treated with 2D cell transplantation - differentiated cell; GTDL: treated withTD + LBP, GE: treated with spheroids; and GEL: treated with spheroid transplantation + LBP.The LBP will be applied immediately after and on the 3rd and 7th days after surgery. Aftertreatments, we will investigate the histological and biomechanical properties of the repairedtendon, such as resistance and elasticity. (AU)