title: Wound-healing effects of low-level laser therapy in diabetic rats involve the modulation of MMP-2 and MMP-9 and the redistribution of collagen types I and III.
abstract: The present study aimed to determine if LLLT restores the balance between mRNA expression of matrix metalloproteinases (MMP-2 and MMP-9) and also the balance between collagen types I and III during the healing process of diabetic wounds. One hundred and twenty male Wistar rats were distributed in Control (untreated non-diabetic rats: UND); Laser (laser treated in non-diabetic rats: LTND); Diabetic (diabetic rats non-laser treated rats: UD); and Diabetic+ Laser (diabetic rats laser treated: DLT) groups. The diabetes model using streptozotocin efficiently induced diabetes, as demonstrated through increased levels of blood glucose. Diode laser (50 mW, 660 nm, 4 J/cm(2), 80 s) was applied a single time after scare induction. Twenty-four hours after LLLT application, rats were euthanized, the scarred areas were collected for MMP-2 and MMP-9 mRNA analysis and also for histological analysis (inflammation and types I and III collagen). The results demonstrated that scare in untreated diabetic rats significantly increased the MMP-2 and MMP-9 expression compared with that in non-diabetic rats (p < 0.05), while LLLT significantly reduced MMP-2 and MMP-9 expression compared with that in untreated diabetic rats (p < 0.05). To conclude, the results also showed that LLLT was able to alter the expression of MMP-9 as well as accelerate the production of collagen and increase the total percentage of collagen type III in diabetic animals.
authors: Graduate Program in Rehabilitation Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil.
authors: Andreia
authors: A
authors: Aparecida Da Silva
authors: Ernesto Cesar Pinto
authors: EC
authors: Leal-Junior
authors: Ana Carolina Araruna
authors: AC
authors: Alves
authors: Caroline Sobral
authors: CS
authors: Rambo
authors: Solange Almeida
authors: SA
authors: Dos Santos
authors: Rodolfo P
authors: RP
authors: Vieira
authors: Paulo De Tarso Camillo
authors: Pde T
authors: De Carvalho
mesh_terms: D000535:Aluminum; D000818:Animals; D024042:Collagen Type I / Q000378:metabolism*; D024061:Collagen Type III / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental; D005708:Gallium; D007204:Indium; D054023:Lasers, Semiconductor; D028022:Low-Level Light Therapy; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D012867:Skin / Q000293:injuries; D014945:Wound Healing / Q000528:radiation effects*
chemical_list: D024042:Collagen Type I; D024061:Collagen Type III; D012333:RNA, Messenger; D007204:Indium; D005708:Gallium; D000535:Aluminum; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9