Arnica montana L. associated with microcurrent accelerates the dermis reorganisation of skin lesions.

The aim of this study was to test the effect of electrical stimulation in association with topical Arnica montana gel on organisational changes in the dermis during tissue repair. An experimental rat incisional skin lesion was used for the study. This involved making an incisional lesion on the dorsum of the animals using a scalpel. Ninety-six animals were used divided into the following groups: control (C), microcurrent (MC); topical treatment with Arnica montana gel (ARN); the ARN + microcurrent (ARN + MC). Treatments were administered daily, and injured tissue samples were collected and processed on Days 2, 6 and 10 for dermis analyses. Myeloperoxidase levels were greater in control than in treatment groups on Days 2 and 6. F4/80 expression was similar among all treatment groups and greater than that in control on Day 2. On Day 6, the expression of vascular endothelial growth factor was higher in the MC group than that in other groups, whereas transforming growth factor-ß expression increased in the MC and ARN + MC groups on Day 10. The expression of matrix metalloproteinase-2 was higher in the ARN + MC group when compared with other groups on Day 10. Expression levels of collagen I were increased in the ARN and ARN + MC groups when compared with control and MC groups on Day 6, while expression of collagen III was enhanced in MC, ARN, and ARN + MC groups when compared with the control. The protocol combining microcurrent with topical application of ARN reduces the inflammatory process, increases myofibroblasts proliferation and decreases the presence of macrophages in the dermis during skin repair in rats.

Acupuncture and moxibustion stimulate fibroblast proliferation and neoangiogenesis during tissue repair of experimental excisional injuries in adult female Wistar rats.

OBJECTIVE: To investigate the effects of acupuncture and moxibustion on the repair of excisional skin injuries on the back of adult female Wistar rats. METHODS: 90 animals were divided into three groups: C, control; A, acupuncture treatment (needled at traditional acupuncture points BL13, BL17 and ST36); M, moxibustion treatment (overlying same traditional acupuncture points). They were euthanased on days 7, 14 and 21 after injury for removal and preparation of tissue for analysis. RESULTS: The treated groups (A and M) showed no changes regarding the structural analysis relative to the control (C) group. The total number of fibroblast cells in the A and M groups were significantly higher than those in the C group on days 14 and 21. The number of granulocytes was significantly less in the A and M groups compared with the C group on days 14 and 21. The total number of newly formed vessels increased on day 21 and was significantly higher in the A and M groups. The amount of birefringent collagen fibre detected on day 21 was significantly higher in the C group. The amount of glycosaminoglycan and hydroxyproline was similar between the groups. The amount of collagen I did not differ between the groups in any period, despite the increased amount detected over time. The amount of type III collagen did not differ between the groups but the detected amount decreased over the course of the experiment. The amount of transforming growth factor ß1 (TGF-ß1) and vascular endothelial growth factor (VEGF) in the A and M rats was similar but inferior to C rats across all experimental periods. CONCLUSIONS: Acupuncture and moxibustion stimulated fibroblast proliferation and neoangiogenesis, and extended the period of collagen fibre reorganisation in the repair of excisional injuries in adult female rats.

Do electrical current and laser therapies improve bone remodeling during an orthodontic treatment with corticotomy?

OBJECTIVES: Evaluate the bone remodeling during orthodontic movement with corticotomy when submitted to low-intensity electrical stimulation application (microcurrent-MC) and low-level laser therapy (LLLT). MATERIAL AND METHODS: One hundred and fifty Wistar rats were divided into the following 5 groups: (C) submitted to tooth movement; (Cort) tooth movement/corticotomy; (Cort-L) tooth movement/corticotomy/laser AsGaAl 808 nm (4.96J/50s); (Cort-Mc) tooth movement/corticotomy/microcurrent (10 µA/5 min); (Cort-L-Mc) tooth movement/corticotomy and laser/microcurrent alternated. Inflammation, angiogenesis, and osteogenesis were evaluated in the periodontal ligament (PDL) and alveolar bone on the 7th, 14th, and 21st days of orthodontic movement. RESULTS: The quantification of inflammatory infiltrate, angiogenesis and expression of TGF-ß1, VEGF, and collagen type I were favorably modulated by the application of therapies such as low-level laser therapy (LLLT), MC, or both combined. However, electrical stimulation increased fibroblasts, osteoclasts and RANK numbers, birefringent collagen fiber organization, and BMP-7 and IL-6 expression. CONCLUSIONS: Low-level laser therapy (LLLT) and MC application both improved the process of bone remodeling during orthodontic treatment with corticotomy. Still, electrical current therapy promoted a more effective tooth displacement but presented expected root resorption similar to all experimental treatments. CLINICAL RELEVANCE: It is important to know the effects of minimally invasive therapies on cellular and molecular elements involved in the bone remodeling of orthodontic treatment associated with corticotomy surgery, in order to reduce the adverse effects in the use of this technique and to establish a safer clinical routine.

Electrical stimulation: Complementary therapy to improve the performance of grafts in bone defects?

The limitations of bone reconstruction techniques have stimulated the tissue engineering for the repair of large bone defects using osteoconductive materials and osteoinductive agents. This study evaluated the effects of low intensity electric current on the inorganic bovine graft in calvaria defects. Bone defects were performed with piezoelectric system in the calvaria of Wistar rats divided into four groups (n = 24): (C) without grafting and without electrical stimulation; (E) with grafting; (MC) without grafting and submitted to electrical stimulation; (MC + E) with grafting and submitted to electrical stimulation. Inflammatory, angiogenic and osteogenic events during bone repair at the 10th, 30th, 60th, and 90th days were considered. Several inflammatory markers demonstrated the efficacy of grafting in reducing inflammation, particularly when subjected to electrical stimulation. Angiogenesis and collagen organization were more evident by electrical stimulation application on the grafts. Moreover, the osteogenic cell differentiation process indicated that the application of microcurrent on grafting modulated the homeostasis of bone remodeling. It is concluded that microcurrent favored the performance of grafts in calvarial rat model. Low-intensity electrical current might improve the osteoconductive property of grafting in bone defects. Therefore, electrical current becomes an option as complementary therapy in clinical trials involving bone surgeries and injuries. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 924-932, 2019.

Differing energy densities with laser 670nm InGaP controls inflammation and collagen reorganization in burns.

PURPOSE: This study compared different energy densities of laser on second degrees burns in rats aiming to determine the most effective dosimetry in stimulation of the healing process. METHODS: Burns were induced in the dorsal skin of 54 animals divided into three groups (n: 18): 1-without treatment; 2-irradiated lesions by the Indium Gallium Phosphide (InGaP) 670nm (4.93J/cm2) laser; 3-irradiated lesions by the InGaP-670nm (9.86J/cm2) laser. Samples were collected on the 2, 10 and 18 days after injury for structural, morphometry, biochemical analysis and Western blotting. RESULTS: The energy densities examined were effective in significantly increasing the total number of fibroblasts and blood vessels and reduce the number of inflammatory cells particularly in irradiated lesions with 9.86J/cm2. This same energy density significantly increased the amount of GAGs (Glycosaminoglycans), decreased the TGF-ß1 (Transforming Growth Factor ß1) and increased the VEGF (Vascular and Endothelial Growth Factor) during the experimental period. This energy density also significantly increased the Collagen type I and decreased Collagen type III and the active isoform of metalloproteinase 9 (MMP-9). CONCLUSIONS: The energy density of 9.86J/cm2 was more effective in promoting cellular responses related to neoangiogenesis, decreasing inflammation and collagen fibers reorganization.

Activity of Porophyllum ruderale leaf extract and 670-nm InGaP laser during burns repair in rats.

BACKGROUND: In this study, we investigated the effects of an extract of the leaves of Porophyllum ruderale and laser irradiation on the healing of burns. METHODS: Seventy-two rats were divided in four groups: untreated controls, treated with laser irradiation, treated with P. ruderale and treated with both P. ruderale and laser irradiation. Burns were produced with a metal plate on the backs of the animals. Wound samples were collected for structural and morphometric analyses and to quantify the expression of TGF-ß1 and VEGF. RESULTS: Laser irradiation increased the number of fibroblasts, collagen fibers and newly formed vessels and decreased the number of granulocytes at the site of the wounds. Densitometric analysis revealed a significant increase in the expression of TGFß-1 in the wounds treated with laser irradiation and with the P. ruderale extract at the beginning of the healing process and a decreased during the experimental period. The expression of VEGF was highlighted in the lesions irradiated with laser alone. CONCLUSION: Inspite of not showing a beneficial effect on the laser combination with the P. ruderale extract, when the laser was used separately, a positive effects to enhance the healing of second-degree burns was promoted. P. ruderale was effective in decreasing the granulocytes during the repair process indicating a possible anti-inflammatory action of this extract of native flora, widely used in folk medicine, but little studied experimentally.

InGaP 670-nm laser therapy combined with a hydroalcoholic extract of Solidago chilensis Meyen in burn injuries.

Therapies that accelerate the healing of burn injuries, improving the quality of life of the patient and reducing the cost of treatment are important. This study evaluated the effects of InGaP 670-nm laser therapy combined with a hydroalcoholic extract of Solidago chilensis leaves on burn wound healing in rats. Seventy-two rats were divided randomly into four groups: control untreated (C), treated with InGaP 670-nm laser with power density of 0.41 W/cm(2) and energy density of 4.93 J/cm(2) (L), treated with S. chilensis extract (S) and treated with S. chilensis extract and laser (LS). Second-degree burns were produced on the back of the animals with metal plate. Wound samples were collected on days 7, 14 and 21 of treatment for structural analysis, morphometry and Western blotting to quantify the expression of transforming growth factor beta 1 (TGF-ß1) and vascular endothelial growth factor (VEGF). The results showed that InGaP laser irradiation at 670 nm alone and combined with extract of S. chilensis promoted significant tissue repair responses in this experimental model, increasing the number of fibroblasts, collagen fibres and newly formed blood vessels throughout the experimental period and decreasing the number of granulocytes in burn wounds of second degree in all treated groups. Exclusive treatment of burn wounds with the hydroalcoholic extract of S. chilensis provided similar quantitative results to those seen in the untreated group throughout the experimental period. Therefore, it was observed in the L and LS groups different responses in the expression of TGF-ß1 and VEGF. The application of 670-nm laser alone or combined with the extract of S. chilensis promoted favourable responses in tissue repair of second-degree burns in this experimental model.

Effects of laser irradiation (670-nm InGaP and 830-nm GaAlAs) on burn of second-degree in rats.

This study investigated the effects of 670-nm indium gallium phosphide (InGaP) and 830-nm gallium aluminum arsenide (GaAlAs) laser therapy on second-degree burns induced on the back of Wistar rats. Sixty-three male Wistar rats were anesthetized, and second-degree burns were made on their back. The animals were then divided randomly into three groups: control (C), animals treated with 670-nm InGaP laser (LIn), and animals treated with 830-nm GaAlAs laser (LGa). The wound areas were removed after 2, 6, 10, 14, and 18 days of treatment and submitted to structural and morphometric analysis. The following parameters were studied: total number of granulocytes and fibroblasts, number of newly formed blood vessels, and percentage of birefringent collagen fibers in the repair area. Morphometric analysis showed that different lasers 670-nm InGaP and 830-nm GaAlAs reduced the number of granulocytes and an increase of newly formed vessels in radiated lesions. The 670-nm InGaP laser therapy was more effective in increasing the number of fibroblasts. The different treatments modified the expression of VEGF and TGF-ß1, when compared with lesions not irradiated. The different types of light sources showed similar effects, improved the healing of second-degree burns and can help for treating this type of injury. Despite the large number of studies with LLTI application in second-degree burns, there is still divergence about the best irradiation parameters to be used. Further studies are needed for developing a protocol effective in treating this type of injury.