scholarly journals Participation of the Immune System and Hedgehog Signaling in Neoangiogenesis Under Laser Photobiomodulation

2019 ◽  
Vol 10 (4) ◽  
pp. 310-316
Author(s):  
Ana Cristina Gonzalez ◽  
Elisângela Trindade Santos ◽  
Tila Fortuna Costa Freire ◽  
Maíra Ferreira Sá ◽  
Zilton de A. Andrade ◽  
...  

Introduction: This study aimed to characterize immune and endothelial cells, myofibroblasts and pericytes, and positive cells for hedgehog proteins in late tissue repair of rats skin wounds treated with 670 nm photobiomodulation therapy (PBMT). Methods: A blind experimental study was conducted, in order to assess the effect of PBMT in later stages of healing, with emphasis on neoangiogenesis, immune cells and Hedgehog signaling. Forty Wistar rats were allocated randomly in two groups; control and treated with a diode GaAlAs laser (9 mW, 670 nm, 0.031 W/cm², spot size of 0.28 cm², fluence of 4 J/ cm2 applied every other day, until a total dose of 16 J/cm2 was achieved). Standardized skin wounds were performed and the animals were euthanized at 14, 21, 28 and 35 days. Tissue sections were subjected to hematoxylin-eosin and immunohistochemistry for CD31, NG2, smooth muscle alpha actin, CD8, CD68, Ptch, Gli-2 and Ihh. All histomorphometric data were statistically analyzed and significance level was at P<0.05. Results: At late stages of wound healing, neoangiogenesis persisted as revealed for the number of CD31+ cells (P=0.016) and NG2+ and smooth muscle alpha actin positive pericytes (P=0.025), for both experimental groups. By day 21, laser-treated group had decreased CD68+ cells (P=0.032) and increased CD8+ (P=0.038). At remodeling stage, there were positive cells for the hedgehog signaling pathway family which seemed to be activated. Conclusion: These data suggest that photobiomodulation therapy was able to modulate extracellular matrix remodelling even at the later stages of wound healing.??

1988 ◽  
Vol 107 (6) ◽  
pp. 2575-2586 ◽  
Author(s):  
D L Ruzicka ◽  
R J Schwartz

The expression of cytoplasmic beta-actin and cardiac, skeletal, and smooth muscle alpha-actins during early avian cardiogenesis was analyzed by in situ hybridization with mRNA-specific single-stranded DNA probes. The cytoplasmic beta-actin gene was ubiquitously expressed in the early chicken embryo. In contrast, the alpha-actin genes were sequentially activated in avian cardiac tissue during the early stages of heart tube formation. The accumulation of large quantities of smooth muscle alpha-actin transcripts in epimyocardial cells preceded the expression of the sarcomeric alpha-actin genes. The accumulation of skeletal alpha-actin mRNAs in the developing heart lagged behind that of cardiac alpha-actin by several embryonic stages. At Hamburger-Hamilton stage 12, the smooth muscle alpha-actin gene was selectively down-regulated in the heart such that only the conus, which subsequently participates in the formation of the vascular trunks, continued to express this gene. This modulation in smooth muscle alpha-actin gene expression correlated with the beginning of coexpression of sarcomeric alpha-actin transcripts in the epimyocardium and the onset of circulation in the embryo. The specific expression of the vascular smooth muscle alpha-actin gene marks the onset of differentiation of cardiac cells and represents the first demonstration of coexpression of both smooth muscle and striated alpha-actin genes within myogenic cells.


1991 ◽  
Vol 99 (3) ◽  
pp. 627-636 ◽  
Author(s):  
C.A. Jahoda ◽  
A.J. Reynolds ◽  
C. Chaponnier ◽  
J.C. Forester ◽  
G. Gabbiani

We have examined the expression of smooth muscle alpha-actin in hair follicles in situ, and in hair follicle dermal cells in culture by means of immunohistochemistry. Smooth muscle alpha-actin was present in the dermal sheath component of rat vibrissa, rat pelage and human follicles. Dermal papilla cells within all types of follicles did not express the antigen. However, in culture a large percentage of both hair dermal papilla and dermal sheath cells were stained by this antibody. The same cells were negative when tested with an antibody to desmin. Overall, explant-derived skin fibroblasts had relatively low numbers of positively marked cells, but those from skin regions of high hair-follicle density displayed more smooth muscle alpha-actin expression than fibroblasts from areas with fewer follicles. 2-D SDS-PAGE confirmed that, unlike fibroblasts, cultured papilla cells contained significant quantities of the alpha-actin isoform. The rapid switching on of smooth muscle alpha-actin expression by dermal papilla cells in early culture, contrasts with the behaviour of smooth muscle cells in vitro, and has implications for control of expression of the antigen in normal adult systems. The very high percentage of positively marked cultured papilla and sheath cells also provides a novel marker of cells from follicle dermis, and reinforces the idea that they represent a specialized cell population, contributing to the heterogeneity of fibroblast cell types in the skin dermis, and possibly acting as a source of myofibroblasts during wound healing.


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