RESUMEN
Tendon healing is impaired in individuals diagnosed with diabetes mellitus (DM). According to research, there is considerable improvement in the healing of surgically tenotomized Achilles tendons following low-level laser therapy (LLLT) in non-diabetic, healthy animals. This study uses light microscopic (LM) and semi-quantitative reverse transcription PCR (RT-PCR) analyses to evaluate the ability of LLLT in healing Achilles tendons from streptozotocin-induced diabetic (STZ-D) rats. A total of 88 rats were randomly divided into two groups, non-diabetic and diabetic. DM was induced in the rats by injections of STZ. The right Achilles tendons of all rats were tenotomized 1 month after administration of STZ. Laser-treated rats were treated with a helium-neon (He-Ne) laser that had a 632.8-nm wavelength and 7.2-mW average power. Experimental group rats received a daily dose of 0.014 J (energy density, 2.9 J/cm(2)). Control rats did not receive LLLT. Animals were sacrificed on days 5, 10, and 15 post-operatively for semi-quantitative LM and semi-quantitative RT-PCR examinations of transforming growth factor-beta1 (TGF-ß1) gene expression. The chi-square test showed that LLLT significantly reduced inflammation in non-diabetic rats compared with their non-diabetic controls (p = 0.02). LLLT significantly decreased inflammation in diabetic rats on days 5 (p = 0.03) and 10 (p = 0.02) compared to the corresponding control diabetic rats. According to the student's t test, LLLT significantly increased TGF-ß1 gene expression in healthy (p = 0.000) and diabetic (p = 0.000) rats compared to their relevant controls. The He-Ne laser was effective in altering the inflammatory reaction and increasing TGF-ß1 gene production.
Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Láseres de Gas/uso terapéutico , Terapia por Luz de Baja Intensidad , Cicatrización de Heridas/efectos de la radiación , Tendón Calcáneo/patología , Tendón Calcáneo/fisiopatología , Tendón Calcáneo/efectos de la radiación , Animales , Diabetes Mellitus Experimental/fisiopatología , Expresión Génica , Masculino , Ratas , Estreptozocina , TranscriptomaRESUMEN
Delayed wound healing is one of the most challenging complications of diabetes mellitus (DM) in clinical medicine. This study has aimed to evaluate the effects of low-level laser therapy (LLLT) on human skin fibroblasts (HSFs) cultured in a high glucose concentration. HSFs were cultured either in a concentration of physiologic glucose (5.5 mM/l) or high glucose media (11.1 and 15 mM/l) for either 1 or 2 weeks after which they were subsequently cultured in either the physiologic glucose or high concentration glucose media during laser irradiation. LLLT was carried out with a helium-neon (He-Ne) laser unit at energy densities of 0.5, 1, and 2 J/cm(2), and power density of 0.66 mW/cm(2) on 3 consecutive days. HSFs' viability and proliferation rate were evaluated with the dimethylthiazol-diphenyltetrazolium bromide (MTT) assay. The LLLT at densities of 0.5 and 1 J/cm(2) had stimulatory effects on the viability and proliferation rate of HSFs cultured in physiologic glucose (5.5 mM/l) medium compared to their control cultures (p = 0.002 and p = 0.046, respectively). All three doses of 0.5, 1, and 2 J/cm(2) had stimulatory effects on the proliferation rate of HSFs cultured in high glucose concentrations when compared to their control cultures (p = 0.042, p = 0.000, and p = 0.000, respectively). This study showed that HSFs originally cultured for 2 weeks in high glucose concentration followed by culture in physiologic glucose during laser irradiation showed enhanced cell viability and proliferation. Thus, LLLT had a stimulatory effect on these HSFs.
Asunto(s)
Terapia por Luz de Baja Intensidad , Piel/efectos de la radiación , Línea Celular , Proliferación Celular/efectos de la radiación , Forma de la Célula/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Medios de Cultivo/química , Complicaciones de la Diabetes/patología , Complicaciones de la Diabetes/radioterapia , Fibroblastos/citología , Fibroblastos/efectos de la radiación , Glucosa/análisis , Humanos , Láseres de Gas/uso terapéutico , Modelos Biológicos , Piel/citología , Cicatrización de Heridas/efectos de la radiaciónRESUMEN
Worldwide, 15% of the 200 million diabetics suffer from diabetic wounds. In 1997, the cost for amputation of toes and limbs that resulted from infected diabetic foot ulcers ranged from $25,000-$40,000 per incident. Increasing numbers of research have shown the positive influence of pentoxifylline (PTX) on healing skin wounds. In this study, we evaluate the effect of systemic PTX (25mg/kg bid) on wound healing in 80 diabetic rats (DB) by secondary intention. Wounds (20 mm × 5 mm) were identically inflicted on the skin area of the backs of all rats. On day 15 following surgery, a band of skin (4 mm × 60 mm) that contained wound was extracted for biomechanical testing. For histologic analysis, both experimental (DB+PTX) and control, receiving distilled water (DB+DW) groups were further subdivided into day 3 and 7 groups. Rats were sacrificed three and seven days after surgery, and a sample from each wound was taken. All specimens were sectioned stereologically and stained with H&E. Cell counts were performed by stereological methods. Semi-quantitative evaluation of matrix metalloproteinases (MMPs) and inhibitor-1 was performed by Reversed Transcription-PCR and UVI TEC software. For statistical analysis we used student's t-test. Collectively, the results of this study demonstrate that there was significant improvement with PTX in all biomechanical parameters. Histologically, PTX reduced inflammation by day seven. Quantitatively, by day five, PTX reduced expression of MMPs and increased TIMP-1 expression. These findings revealed that PTX significantly improved wound healing indices in streptozotocin-induced DB.
Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Pentoxifilina/farmacología , Piel/efectos de los fármacos , Piel/fisiopatología , Cicatrización de Heridas/efectos de los fármacos , Animales , Fenómenos Biomecánicos , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/metabolismo , Recuento de Células , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Epitelio/efectos de los fármacos , Epitelio/patología , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Masculino , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 3 de la Matriz/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Ratas , Ratas Wistar , Inhibidor Tisular de Metaloproteinasa-1/metabolismoRESUMEN
Diabetes is one of the most common causes of delayed wound healing. Low-level laser therapy (LLLT) are one of the therapeutic modalities used for the treatment of wounds. The aim of present study is to evaluate the effect of LLLT in experimentally-induced diabetic rats. Two full thickness skin incisions were made on dorsal regions of each rat. The wounds were randomly divided into laser-treated and placebo. Laser-treated wounds of the healthy (non-diabetic) animals were submitted to a pulsed-infrared 890nm laser with an 80Hz frequency and 0.03J/cm(2) for each wound point in the first healthy group and 0.2J/cm(2) in the second healthy group. Laser-treated wounds of the diabetic animals received the same pulsed-infrared laser treatments as the second group for each wound point. On day 15, a sample from each wound was extracted and submitted for tensile strength evaluation. Laser irradiation with 0.03J/cm(2) significantly decreased the maximum load for wound repair in healthy rats (p=0.015). Laser irradiation with 0.2J/cm(2) significantly increased the maximum load in wounds from the healthy control (p=0.021) and diabetic (p<001) groups. Laser treatments with a pulsed infrared laser at 0.2J/cm(2) significantly accelerated wound healing in both healthy and diabetic rats.