Effect of photobiostimulation on peripheral neuropathy of rats with type 1 diabetes mellitus induced by streptozotocin.

Author(s)

Igor Rafael Correia Rocha

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas
• Defense date: 11 dez. 2017

Examining board members

Marucia Chacur; Cristiane Jaciara Furlaneto; Simone Cristina Motta; Alice Cristina Rodrigues

• Advisor: Marucia Chacur

Abstract

Diabetes mellitus is a chronic disease with more than 3,500 years of history in which its first description is found in the oldest medical treatise written by the Egyptian civilization, the Ebers papyrus. Diabetes mellitus is a metabolic syndrome characterized by a significant increase in glucose levels in the bloodstream, a condition known as hyperglycemia. The hyperglycemic state damages the peripheral nerve fibers structurally and physiologically, causing peripheral diabetic neuropathy (degenerative process). This neuropathy leads to the patient, a life full of limitations and incapacities. The main complaints regarding peripheral diabetic neuropathy are chronic pain, motor impairment and significant lack of sensation in the peripheral limbs, resulting fatally in some situations with lower limb amputation. It should be mentioned that there is no treatment in the clinic with a focus on the peripheral degeneration caused by type 1 diabetes mellitus, as there is no effective treatment for the improvement of the nociceptive (pain) situation, hence the need for research on other therapeutic modalities that return and restore quality of life of those affected by this disease. In this project, the model of diabetic peripheral neuropathy due to type 1 diabetes mellitus induced by the administration of streptozotocin was used and the proposed technique of laser therapy to interfere in the process of degeneration of the peripheral nerve fibers as well as in the improvement of the nociceptive ) analyzed by the models of tactile allodynia, mechanical hyperalgesia and thermal hyperalgesia before, during and after the proposed treatment. The present study demonstrated that the laser therapy technique as a treatment proposal for peripheral diabetic neuropathy in an animal model of type 1 diabetes mellitus induced by streptozotocin in addition to improving the nociceptive condition (pain) was able to modulate some pro-and anti-inflammatory cytokines (interleukins) (TNFα, IL-6, IL-10) on the sciatic nerve of diabetic rats treated with said technique. Still, in relation to peripheral nerve fibers, the laser therapy technique reversed the degenerative process of these fibers, represented by the modulation of the laminin and zero protein structural proteins. The laser therapy technique was also capable of modulating advanced glycation end-receptor (RAGE) receptors, an important activating component of the NF-κB nuclear transcription factor responsible for inducing the release of proinflammatory cytokines (interleukins) in rats\' sciatic nerve diabetics. The results showed a significant efficacy of the laser therapy technique as a useful proposal for the treatment of peripheral diabetic neuropathy. However, further studies are needed to better elucidate the molecular mechanisms that measure the therapeutic effect of the laser therapy technique. (AU)

• FAPESP's process: 16/00038-6 - Photobiostimulation effect on peripheral neuropathy in rats with type 1 diabetes induced by streptozotocin
• Grantee: Igor Rafael Correia Rocha
• Support type: Scholarships in Brazil - Master