severe-burn-injury-in-a-swine-model-for-clinical-dressing-assessment

Severe Burn Injury in a Swine Model for Clinical Dressing Assessment

Wound healing is a dynamic repair process and is the most complex biological process in human life. In response to burn injury, alterations in biological ...

wet-spinning-based-molding-process-of-gelatin-for-tissue-regeneration

Wet-spinning-based Molding Process of Gelatin for Tissue Regeneration

This article presents an inexpensive method to fabricate gelatin, as a natural polymer, into monofilament fibers or other appropriate forms. Through the ...

National Defense Medical Center

National Defense Medical University

Hypertrophic scarring is related to persistent activation of transforming growth factor-β (TGF-β)/Smad signaling. In the TGF-β/Smad signaling cascade, the TGF-β type I receptor (TGFBRI) phosphorylates Smad proteins to induce fibroblast proliferation and extracellular matrix deposition. In this study, we inhibited TGFBRI gene expression via TGFBRI small interfering RNA (siRNA) to reduce fibroblast proliferation and extracellular matrix deposition. Our results demonstrate that downregulating TGFBRI expression in cultured human hypertrophic scar fibroblasts significantly suppressed cell proliferation and reduced type I collagen, type III collagen, fibronectin, and connective tissue growth factor (CTGF) mRNA, and type I collagen and fibronectin protein expression. In addition, we applied TGFBRI siRNA to wound granulation tissue in a rabbit model of hypertrophic scarring. Downregulating TGFBRI expression reduced wound scarring, the extracellular matrix deposition of scar tissue, and decreased CTGF and α-smooth muscle actin mRNA expression in vivo. These results suggest that TGFBRI siRNA could be applied clinically to prevent hypertrophic scarring. 

siRNA-targeting transforming growth factor-β type I receptor reduces wound scarring and extracellular matrix deposition of scar tissue.

Cartilage is exposed to compression forces during joint loading. Therefore, exogenous stimuli are frequently used in cartilage tissue engineering strategies to enhance chondrocyte differentiation and extracellular matrix (ECM) secretion. In this study, human adipose-derived stem cells were seeded on a gelatin/polycaprolactone scaffold to evaluate the histochemical and functional improvement of tissue-engineered cartilage after hyperbaric oxygen/air treatment in a rabbit articular defect model. Behavior tests showed beneficial effects on weight-bearing and rear leg-supporting capacities after treatment of tissue-engineered cartilage with 2.5 ATA oxygen or air. Moreover, positron emission tomography images and immunohistochemistry staining demonstrated hydroxyapatite formation and increased ECM synthesis, respectively, at the tissue-engineered cartilage graft site after high pressure oxygen/air treatment. Based on these results, we concluded that hyperbaric oxygen and air treatment can improve the quality of tissue-engineered cartilage in vivo by increasing the synthesis of ECM. 

Histochemical and functional improvement of adipose-derived stem cell-based tissue-engineered cartilage by hyperbaric oxygen/air treatment in a rabbit articular defect model.

Autologous skin transplantation is a common treatment for patients with full-thickness burns. Postoperative wound care is essential for skin graft donor and recipient sites, but traditional wound dressings such as cotton and gauze do not form an effective barrier to bacteria, and patients can feel uncomfortable when replacing dressings.

Evaluation of Wound Healing Efficacy of an Antimicrobial Spray Dressing at Skin Donor Sites.

Heart failure (HF) is the leading cause of death in the world and digoxin remains one of the oldest therapies for HF. However, its safety and efficacy have been controversial since its initial use and there is uncertainty about its long-term efficacy and safety. Recently, the repositioning of cardiac glycosides is to function in anti-tumor activity via multiple working pathways. It is interesting to compare the potential effects of digoxin in clinical patients and cell lines. First, we analyze patient information retrieved from the National Health Insurance Research database of Taiwan between January 1, 2000 and December 31, 2000. This retrospective study included a study cohort (1,219 patients) and a comparison cohort. Our analytical data suggested that patients taking digoxin are at an increased risk of cancers, including breast, liver, and lung cancers, during the 10-year follow-up period. In contrast to the anti-tumor function of digoxin, we further examined the potential pathway of digoxin via the cell-based strategy using several breast cancer cell lines, including MCF-7, BT-474, MAD-MB-231, and ZR-75-1. Digoxin consistently exerted its cytotoxicity to these four cell lines with various range of concentration. However, the proliferation of ZR-75-1 cells was the only cell lines induced by digoxin and the others were dramatically suppressed by digoxin. The responsiveness of SRSF3 to digoxin might be involved with cell-type differences. In summary, we combined a cohort study for digoxin treatment for HF patients with a cell-based strategy that addresses the translation issue, which revealed the complexity of personalized medicine.

Risk of cancer in patients with heart failure who use digoxin: a 10-year follow-up study and cell-based verification.

Glioblastoma multiforme (GBM) is the most common primary central nervous system malignant tumor. It responds poorly to standard therapies, such as surgical resection, radiation therapy and chemotherapy. Many chemotherapeutic drugs are focused on apoptosis induction and radiation sensitivity. Inhibition of histone acetylation via histone deacetylase inhibitor (HDACI) is one such strategy. Statins (or 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors) are classical drugs used to lower cholesterol but also inhibitors of histone deacetylation activity. This study analyzes the combinatory effects of valproic acid (VPA) and fluvastatin on apoptosis induction in GBM8401 cells. The results show that they act synergistically in inducing γ-H2AX and apoptosis accompanied by higher acetylated histones H3 and H4. Downregulation of p53 occurred by VPA alone and fluvastatin alone, but not at their combined application; upregulation of p21 at the protein level was induced by each of the drugs alone and no further increase occurred at combined application. The drug BEZ235 inhibited phosphorylation of Akt and attenuated the level of γ-H2AX as well as cleaved PARP (cPARP) induced at combined application of VPA and fluvastatin. Induction of apoptosis within a 48h incubation period was massive when measured as the subG1 peak (97%) and was detected after a 24h incubation at low level when assayed with PE Annexin V. Synergistic apoptosis induction was demonstrated also after 24h incubation by the appearance of cPARP. Partial silencing of p21 reduced cPARP as well as the percentage of apoptotic cells in the subG1 peak. However, partial silencing of p53 had no effect on apoptosis. Such findings offer a better understanding of the mechanism of action of HDACIs in combination with statins that may guide the development of a new combinatory reposition for the treatment of GBM.

The synergistic effects of valproic acid and fluvastatin on apoptosis induction in glioblastoma multiforme cell lines.

Significant skin pigmentation changes occur when patients suffer deep burn injuries. These pigmentation disorders may cause not only cosmetic and psychological issues, but more importantly it increases the risk of skin cancer or photoaging. Severe burns significantly effect on the process of repigmentation as the pigmentation is tightly regulated by cell proliferation and differentiation of melanocytes and melanocyte stem cells which are housing in the epidermis and hair follicles of the skin. In the present review, we discuss the possible mechanisms to replenish the melanocytes from the healthy epidermis and hair follicles surrounding burn wounds. The molecular mechanisms of skin repigmentation following healing of burn injuries includes the differentiation of melanoblasts into melanocytes, the distribution and responses of melanocytes and melanocyte stem cells after burn injury, and the regulation of melanin production. We also reviewed advanced therapeutic strategies to treat pigmentation disorders, such as convectional surgery, laser, UV treatment and emerging concepts in skin tissue-engineering.

Restoration of skin pigmentation after deep partial or full-thickness burn injury.

Caffeine, theophylline, and theobromine are the most well-known members of methylxanthines. Caffeine-induced serine/arginine-rich splicing factor 2, SRSF2, and SRSF3 are required for the alternative splicing of a subset of cancer-associated genes. However, it remains to be investigated whether and how theophylline and theobromine as well as caffeine exert their antitumor effects through mediating the alternative splicing process. Here, we reveal that theophylline down-regulated  expression and switched  from alpha into a beta isoform as caffeine did in HeLa and MCF-7 cells via the reverse-transcriptase polymerase chain reaction and Western blot analysis. Further functional studies show that theophylline induced cellular apoptosis, senescence, and decreased colony formation. Interestingly, theophylline had a suppressive effect on cellular proliferation, whereas caffeine enhanced cellular proliferation rates via the 5-bromo-2-deoxyuridine analysis. Theophylline and caffeine had no effect on MCF-10A cells, which is a normal breast cell line. Our results provide an insight that theophylline as well as caffeine could be repurposed as antitumor leading compounds via the downregulation of splicing factor SRSF3 and its target genes.

Theophylline exhibits anti-cancer activity  suppressing SRSF3 in cervical and breast cancer cell lines.

Repair and regeneration of craniofacial tissues is particularly challenging because they comprise a complex structure of hard and soft tissues involved in intricate functions. This study combined collagen scaffolds and human adipose stem cells (hASCs) for oral mucosal and calvarial bone regeneration by using resveratrol (RSV), which affects the differentiation of mesenchymal stem cells. We have evaluated the effect of collagen scaffold-containing RSV (collagen/RSV) scaffolds both in vitro and in vivo for their wound healing and bone regeneration potential. Scanning electron microscopy and immunostaining results reveal that hASCs adhere well to and proliferate on both collagen scaffolds and collagen/RSV scaffolds. Oral mucosal lesion experiments demonstrated that the collagen/RSV scaffold is more effective in wound closure and contraction than the collagen scaffold. The micro-computed tomography (μCT) images of calvarial bone display regenerating bone in defects covered with hASCs on collagen/RSV scaffolds that are more visible than that in defects covered with hASCs on a collagen scaffolds. RSV was more effective at inducing hASC differentiation on the collagen scaffold, suggesting that collagen/RSV scaffolds can provide useful biological cues that stimulate craniofacial tissue formation.

Combination of resveratrol-containing collagen with adipose stem cells for craniofacial tissue-engineering applications.

Amiodarone is a widely used class III antiarrhythmic agent which prolongs the action potential and refractory period by blockage of several types of myocardial potassium channels. Emerging evidence suggests that amiodarone sensitize tumor cells in response to chemotherapy. Nevertheless, little is known about the underlying molecular mechanism. To gain further insight, we demonstrated that amiodarone accumulated the population of a premature termination codon-containing isoform of serine and arginine rich splicing factor 3 () without increasing alternative spliced  isoform. Amiodarone enhanced reactive oxygen species production and increased cell apoptosis, whereas reduced DNA damage. Moreover, amiodarone suppressed miR-224 and increased its target  expression. Taken together, our results suggested amiodarone caused cancer cell death might be through increased  and miR-224 reduction in a p53-independent manner.

Amiodarone promotes cancer cell death through elevated truncated SRSF3 and downregulation of miR-224.

To treat skin color disorders, such as vitiligo or burns, melanocytes are transplanted for tissue regeneration. However, melanocyte distribution in the human body varies with age and location, making it difficult to select the optimal donor skin to achieve a desired color match. Determining the correlations with the desired skin color measurement based on CIELAB color, epidermal melanocyte numbers, and melanin content of individual melanocytes is critical for clinical application.

High correlation between skin color based on CIELAB color space, epidermal melanocyte ratio, and melanocyte melanin content.

Skin substitutes with existing vascularization are in great demand for the repair of full-thickness skin defects. In the present study, we hypothesized that a pre-vascularized skin substitute can potentially promote wound healing. Novel three-dimensional (3D) skin substitutes were prepared by seeding a mixture of human endothelial progenitor cells (EPCs) and fibroblasts into a human plasma/calcium chloride formed gel scaffold, and seeding keratinocytes onto the surface of the plasma gel. The capacity of the EPCs to differentiate into a vascular-like tubular structure was evaluated using immunohistochemistry analysis and WST-8 assay. Experimental studies in mouse full-thickness skin wound models showed that the pre-vascularized gel scaffold significantly accelerated wound healing 7 days after surgery, and resembled normal skin structures after 14 days post-surgery. Histological analysis revealed that pre-vascularized gel scaffolds were well integrated in the host skin, resulting in the vascularization of both the epidermis and dermis in the wound area. Moreover, mechanical strength analysis demonstrated that the healed wound following the implantation of the pre-vascularized gel scaffolds exhibited good tensile strength. Taken together, this novel pre-vascularized human plasma gel scaffold has great potential in skin tissue engineering.

ArticleTotal : 2	Year
Publication title Cited by 5	2018
Publication title Cited by 5	2019

Article	Year
siRNA-targeting transforming growth factor-β type I receptor reduces wound scarring and extracellular matrix deposition of scar tissue. The Journal of investigative dermatology\| PubMed ID: 24670383	2014
Histochemical and functional improvement of adipose-derived stem cell-based tissue-engineered cartilage by hyperbaric oxygen/air treatment in a rabbit articular defect model. Annals of plastic surgery\| PubMed ID: 25695443	2015
Evaluation of Wound Healing Efficacy of an Antimicrobial Spray Dressing at Skin Donor Sites. Wounds : a compendium of clinical research and practice\| PubMed ID: 26284376	2015
Risk of cancer in patients with heart failure who use digoxin: a 10-year follow-up study and cell-based verification. Oncotarget\| PubMed ID: 28496002	2017
The synergistic effects of valproic acid and fluvastatin on apoptosis induction in glioblastoma multiforme cell lines. The international journal of biochemistry & cell biology\| PubMed ID: 29017950	2017
Restoration of skin pigmentation after deep partial or full-thickness burn injury. Advanced drug delivery reviews\| PubMed ID: 29079536	2018
Theophylline exhibits anti-cancer activity suppressing SRSF3 in cervical and breast cancer cell lines. Oncotarget\| PubMed ID: 29254178	2017
Combination of resveratrol-containing collagen with adipose stem cells for craniofacial tissue-engineering applications. International wound journal\| PubMed ID: 29536622	2018
Amiodarone promotes cancer cell death through elevated truncated SRSF3 and downregulation of miR-224. Oncotarget\| PubMed ID: 29568365	2018
High correlation between skin color based on CIELAB color space, epidermal melanocyte ratio, and melanocyte melanin content. PeerJ\| PubMed ID: 29844968	2018
Development of a Novel Pre-Vascularized Three-Dimensional Skin Substitute Using Blood Plasma Gel. Cell transplantation\| PubMed ID: 30203684	2018

Yi-Wen Wang

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