Hong-Wei Liu

Helium-Neon Laser Irradiation Promotes the Proliferation and Migration of Human Epidermal Stem Cells In Vitro: Proposed Mechanism for Enhanced Wound Re-epithelialization

OBJECTIVE The present study was conducted to investigate the effects of helium-neon (He-Ne) laser irradiation on the proliferation, migration, and differentiation of cultured human epidermal stem cells (ESCs). BACKGROUND DATA A He-Ne laser with a wavelength of 632.8 nm is known to have photobiological effects, and is widely used for accelerating wound healing; however, the cellular mechanisms involved have not been completely understood. METHODS The ESCs were prepared from human foreskin, and irradiated by using He-Ne laser at 632.8 nm with 2 J/cm(2). The ESC proliferation, migration, and differentiation were examined by using XTT assay, scratch assay, and flow cytometry technology, respectively. The phosphorylation of extracellular signal-regulated kinases (ERK) was analyzed by using Western blotting. RESULTS He-Ne laser irradiation markedly promoted cell proliferation and migration accompanied by an increase in the phosphorylation of ERK, but did not significantly influence cell differentiation. CONCLUSION Our data indicated that photostimulation with a He-Ne laser resulted in a significant increase in human ESC proliferation and migration in vitro, which might contribute, at least partially, to accelerated wound re-epithelialization by low-level laser therapy.

Evaluation of 2 Purification Methods for Isolation of Human Adipose-Derived Stem Cells Based on Red Blood Cell Lysis With Ammonium Chloride and Hypotonic Sodium Chloride Solution

Background The present study was conducted to compare 2 purification methods for isolation of human adipose-derived stromal vascular fraction or stem cells (ADSCs) based on red blood cell (RBC) lysis with 155 mM ammonium chloride (NH4Cl) and hypotonic sodium chloride (NaCl) solution, and try to develop a safe, convenient, and cost-effective purification method for clinical applications. Methods Adipose-derived stem cells and RBC were harvested from the fatty and fluid portions of liposuction aspirates, respectively. The suitable concentration of hypotonic NaCl solution on RBC lysis for purification of ADSCs was developed by RBC osmotic fragility test and flow cytometry analysis. The effects of 155 mM NH4Cl or 0.3% NaCl solution on ADSCs proliferation and RBC lysis efficiency were examined by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide assay and lysis efficiency test, respectively. In addition, the adipogenic and osteogenic capabilities, phenotype and genetic stability of ADSCs were evaluated by oil red staining, alkaline phosphatase activity measurement, flow cytometry, and karyotype analysis, respectively. Results Sodium chloride solution in 0.3% concentration effectively removed RBCs and did not influence the survival of ADSCs in the 10-minute incubation time. The lysis efficiency did not differ significantly between 0.3% NaCl and 155 mM NH4Cl. Moreover, the adipogenic and osteogenic capabilities, surface marker expression and karyotype of the ADSCs were not affected by lysis solutions or by lysis per se. However, the proliferation capacity in the 0.3% NaCl group was superior to that in 155 mM NH4Cl group. Conclusions Our data suggest that 0.3% NaCl solution is useful for isolating ADSCs from liposuction aspirate for clinical applications with safety, convenience, and cost-effect.

Facial intramuscular lipoma occurrence following topical cosmetic injection with a mixture of basic fibroblast growth factor: A report of two cases

ABSTRACT Growth factors and cytokines control cell growth, proliferation and differentiation via a network of inter- and intracellular signalling pathways, and are involved in skin self-renewing and wound healing. In recent years, topical and injectable growth factors and cytokines have emerged as an intriguing therapeutic modality that can be harnessed for aesthetic purposes. However, very little data are available on their long-term safety and tolerability. In this report, we describe two cases of patients, who developed intramuscular lipoma of the chin following topical injection with a mixture of basic fibroblast growth factor as the main ingredients for chin augmentation. Biopsies in the two cases were performed at our department, and revealed intramuscular lipoma. Our report indicates that the topical injection of growth factors can lead to tumorigenesis, so health care providers need to be aware of its potential consequences.

Effects of topical oxygen therapy on ischemic wound healing.

[Purpose] This study evaluated the effects of topical oxygen therapy on the hind limb wounds of rats under ischemic conditions. [Subjects and Methods] Twelve injured rats were treated with topical oxygen on skin wounds located on the hind limb and compared with twelve injured control rats. Indexes including gross morphology of the wound, wound healing time, wound healing rate, and histological and immunohistochemical staining of sections of wound tissue were examined at different time points after intervention. [Results] The wound healing time was shorter in the topical oxygen therapy group than the control group. The wound healing rate and granulation tissue formation in the topical oxygen therapy group showed significant improvement on days 3, 7, and 14. Through van Gieson staining, the accumulation of collagen fiber in the topical oxygen therapy group was found to have improved when compared with the control group on day 7. Through semiquantitative immunohistochemical staining, many more new vessels were found in the topical oxygen therapy group compared with the model control group on day 7. [Conclusion] The results of the experiment showed that topical oxygen therapy improved ischemic wound healing.

Improved fat transplantation survival by using the conditioned medium of vascular endothelial growth factor transfected human adipose-derived stem cells

Autologous fat transplantation has been applied widely in clinic. However, the low survival rate is still a problem to be solved. Studies shows that the human adipose‐derived stem cells (ADSCs) transfected by vascular endothelial growth factor (VEGF) can improve the survival rate of autologous fat transplantation. Our study is to evaluate the effects of the conditioned medium of VEGF‐transfected human adipose‐derived stem cells (VEGF‐ADSCs‐CM) on fat transplantation. ADSCs were isolated and transfected with MOI = 40. The study was divided into three groups, VEGF‐ADSCs‐CM group, normal‐ADSCs‐CM group and control group. The conditioned media for VEGF‐ADSCs‐CM group and normal‐ADSCs‐CM group were collected, and then mixed with fat, with the mixtures being injected into the back of nude mice. On 4, 7, 15, 30, 60 days after transplantation, the grafts were evaluated on the wet weight, histology, ELISA and western blot. As the results revealed, the survival rate of VEGF‐ADSCs‐CM group was highest with the best fat cell morphology, and the VEGF secretion of VEGF‐ADSCs‐CM group was also highest. Therefore, our study demonstrates that VEGF‐ADSCs‐CM can improve the survival rate of fat transplantation effectively, and VEGF‐ADSCs‐CM can be regarded as an effective assisted method for fat transplantation.

Preconditioning With Low-Level Laser Irradiation Enhances the Therapeutic Potential of Human Adipose-derived Stem Cells in a Mouse Model of Photoaged Skin

This study was conducted to explore the therapeutic potential of human adipose‐derived stem cells (ADSCs) irradiated with a low‐level laser (LLL). Cultured ADSCs were treated with 650‐nm GaAlAs laser irradiation at 2, 4 and 8 J cm−2. Cell proliferation was quantified by MTT assays, cytokine secretion was determined by enzyme‐linked immunosorbent assays, and adipogenic differentiation was examined by oil red O staining. Additionally, the expression profiles of putative ADSC surface markers were analyzed by quantitative real‐time PCR. In addition, a mouse photoaged skin model was established by UVB irradiation. Effects of GaAlAs laser–treated ADSCs on the thicknesses of the epidermis and dermis were analyzed by hematoxylin and eosin staining. The results showed that GaAlAs laser treatment of cells at a radiant exposure of 4 J cm−2 enhanced ADSC proliferation and adipogenic differentiation and increased secretion of growth factors. Furthermore, GaAlAs laser irradiation upregulated the expression of putative ADSC surface markers. In the mouse model of photoaged skin, ADSCs treated with GaAlAs laser irradiation had markedly decreased the epidermal thickness and increased the dermal thickness of photoaged mouse skin. Our data indicate that LLL irradiation is an effective biostimulator of ADSCs and might enhance the therapeutic potential of ADSCs for clinical use.