Biochemical changes in injured sciatic nerve of rats after low-level laser therapy (660nm and 808nm) evaluated by Raman spectroscopy

Author(s)

Melo Maciel Mangueira, Melissa de Almeida ^[1] ; Mangueira, Nilton Maciel ^[2] ; Gama Filho, Ozimo Pereira ^[2] ; de Oliveira, Marcio Moyses ^[2] ; Heluy, Renato Albuquerque ^[2] ; Silveira, Jr., Landulfo ^[3] ; Moniz de Aragao Daquer, Egas Caparelli ^[4]

Affiliation

^[1] Fac Santa Terezinha CEST, Dept Physiotherapy, Sao Luis, Maranhao - Brazil

^[2] Univ Fed Maranhao UFMA, Dept Morphol, Cidade Univ Dom Delgado, Ave Portugueses 1966, BR-65080805 Sao Luis, Maranhao - Brazil

^[3] Univ Anhembi Morumbi UAM, Ctr Innovat Technol & Educ CITE, Parque Tecnol Sao Jose do Campos, BR-12247016 Sao Paulo - Brazil

^[4] Univ Estado Rio De Janeiro, Roberto Alcantara Gomes Biol Inst, Dept Physiol Sci, Ave Prof Manuel de Abreu, 444-5 Andar, BR-20550170 Rio De Janeiro, RJ - Brazil

• Document type: Journal article
• Source: Lasers in Medical Science; v. 34, n. 3, p. 525-535, APR 2019.
• Web of Science Citations: 0

Abstract

The aim of this study was to identify biochemical changes in sciatic nerve (SN) after crush injury and low-level laser therapy (LLLT) with 660nm and 808nm by Raman spectroscopy (RS) analysis. A number of 32 Wistar rats were used, divided into four groups (control 1, control 2, LASER 660nm, and LASER 808nm). All animals underwent surgical procedure of the SN and groups control 2, LASER 660nm, and LASER 808nm were submitted to SN crush damage (axonotmesis). The LLLT in the groups LASER 660nm and LASER 808nm was applied daily for 21 consecutive days (100mW, 30s, 133J/cm(2) fluence). The hind paw was removed and the SN was dissected and positioned on an aluminum support to collect dispersive Raman spectra (830nm excitation, 30s accumulation). To estimate the biochemical changes in the SN associated with LLLT, the principal component analysis (PCA) was applied. The Raman spectra of the sciatic nerve fragments showed peaks of the major biochemical components of the nerve, especially sphingolipids, phospholipids, glycoproteins, and collagen. The spectral features identified in some of the principal component loading vectors are referred to the biochemical elements present on the SN and were increased in the groups treated with LLLT, mainly lipids (sphingo and phospholipids) and proteins (collagen)constituents of the myelin sheath. The RS was effective in identifying the biochemical differences in the SN after the crush injury, and LASER 660nm was more efficient than the LASER 808nm in cell proliferation and repair of the injured SN. (AU)

• FAPESP's process: 09/01788-5 - Dispersive Raman spectroscopy using optical fibers "Raman probe" applied to the diagnosis of neoplasia in the skin and prostate
• Grantee: Landulfo Silveira Junior
• Support Opportunities: Regular Research Grants