Edge Effect: The Role of Collagen in Wound Healing

Complexed Polymer Film-Forming Spray: An Optimal Delivery System for Secretome of Mesenchymal Stem Cell as Diabetic Wound Dressing?

Diabetes-related wounds have physiological factors that make healing more complicated. High sugar levels can increase microbial infection risk while limiting nutrition and oxygen transfer to the wound area. The secretome of mesenchymal stem cells has been widely known for its efficacy in regenerative therapy. However, applying the secretome directly to the wound can reduce its effectiveness. In this review, we examined the literature on synthesizing the combinations of carboxymethyl chitosan, hyaluronic acid, and collagen tripeptides, as well as the possibility of physicochemical properties enhancement of the hydrogel matrix, which could potentially be used as an optimal delivery system of stem cell's secretome for diabetic wound healing.

Collagen-based formulations for wound healing: A literature review

Wounds have always been the point of concern owing to the involvement of infections and the level of severity. Therefore, the management of wounds always requires additional effort for comprehensive healing and subsequent removal of the scar from the wound site. The role of biomaterials in the management of chronic wounds has been well established. One of such biomaterials is collagen (Col) that is considered to be the crucial component of most of the formulations being developed for wound healing. The role of Col extracted from marine invertebrates remains an unmarked origin of the proteinaceous constituent in the evolution of innovative pharmaceuticals. Col is a promising, immiscible, fibrous amino acid of indigenous origin that is ubiquitously present in extracellular matrices and connective tissues. There are different types of Col present in the body such as type I, II, III, IV, and V however the natural sources of Col are vegetables and marine animals. Its physical properties like high tensile strength, adherence nature, elasticity, and remodeling contribute significantly in the wound healing process. Col containing formulations such as hydrogels, sponges, creams, peptides, and composite nanofibers have been utilized widely in wound healing and tissue engineering purposes truly as the first line of defense. Here we present the recent advancements in Col based dosage forms for wound healing. The Col based market of topical preparations and the published reports identify Colas a useful biomaterial for the delivery of pharmaceuticals and a platform for tissue engineering.

Healing Process of Rat Skin Wounds Treated With Vitamin C and Low-Intensity Laser Therapy

INTRODUCTION

This study evaluated, from a histological point of view, the process of repairing skin wounds caused in the dorsal region of rats when subjected to treatment with vitamin C, low-intensity laser, and association of both.

METHODS

Forty-eight adult male rats (Rattus norvegicus, albinus, Wistar), weighing between 250 and 300 g were used in this study. The rats were anesthetized with sodium pentobarbital (10 mg/kg) intraperitoneally (IP) and a circular area of ​​skin of approximately 8 mm in diameter was removed from the dorsal region of their back by a punch. The animals were randomly divided into four groups of 12 individuals: Group I, control group, was treated with saline solution; Group II was treated with topical application of vitamin C; Group III was treated with low-intensity laser; and Group IV was treated with both low-intensity laser and topical application of vitamin C. Samples were histologically analyzed through optical microscopy with hematoxylin and eosin staining and collagen I and III concentrations were quantified using the picrosirius-hematoxylin histochemical method and further submitted to statistical analysis.

RESULTS

Whilst the control and vitamin C groups admittedly showed slight epithelial proliferation at the wound edges, the group irradiated with low-intensity laser and the group treated with both laser and vitamin C had already partially formed epidermis, with a more organized underlying connective tissue and less evident inflammatory process. The group treated with laser alone obtained a higher concentration of type I collagen fibers and the group with the highest amount of type III collagen fibers was the one treated with the association of vitamin C and laser.

CONCLUSION

The present findings suggest that in spite of all treatments being effective in the repair of skin wounds compared to the control group, the isolated use of low-intensity therapy laser and its combined use with topical vitamin C showed the most favorable results, indicating that those could be further used for the treatment of skin wounds.

Comprehensive Review of Hybrid Collagen and Silk Fibroin for Cutaneous Wound Healing

The use of hybridisation strategy in biomaterials technology provides a powerful synergistic effect as a functional matrix. Silk fibroin (SF) has been widely used for drug delivery, and collagen (Col) resembles the extracellular matrix (ECM). This systematic review was performed to scrutinise the outcome of hybrid Col and SF for cutaneous wound healing. This paper reviewed the progress of related research based on in vitro and in vivo studies and the influence of the physicochemical properties of the hybrid in wound healing. The results indicated the positive outcome of hybridising Col and SF for cutaneous wound healing. The hybridisation of these biomaterials exhibits an excellent moisturising property, perfectly interconnected structure, excellent water absorption and retention capacity, an acceptable range of biodegradability, and synergistic effects in cell viability. The in vitro and in vivo studies clearly showed a promising outcome in the acceleration of cutaneous wound healing using an SF and Col hybrid scaffold. The review of this study can be used to design an appropriate hybrid scaffold for cutaneous wound healing. Therefore, this systematic review recapitulated that the hybridisation of Col and SF promoted rapid cutaneous healing through immediate wound closure and reepithelisation, with no sign of adverse events. This paper concludes on the need for further investigations of the hybrid SF and Col in the future to ensure that the hybrid biomaterials are well-suited for human skin.

In vitro wound healing potency of methanolic leaf extract of Aristolochia saccata is possibly mediated by its stimulatory effect on collagen-1 expression

Background

Identification and assessment of therapeutic potential of natural products derived from medicinal plants have led to the discovery of innovative and economical drugs to treat several diseases, including chronic wounds. In vitro cell based scratch assay is an appropriate and inexpensive method for initial understanding of wound healing potential of medicinal plant extracts. The current study was aimed at investigating the wound healing capacity of Aristolochia saccata leaf extract by using scratch assay as a primary model, where proliferative and migratory capabilities of test compounds could be monitored through microscopy studies. A. saccata is an evergreen climbing shrub belongs to the family Aristolochiaceae.

Methods

Methanolic extraction of the plant material was done using Soxhlet apparatus and the cytotoxicity of the extract on L929 cells was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. L929 is a human fibroblast cell line. In vitro scratch assay was performed to evaluate the wound healing properties of A. saccata leaf extract and possible mechanism of action was analyzed by flow cytometric expression studies of an extracellular matrix (ECM) factor, collagen type-1.

Results

MTT assay revealed that A. saccata leaf extract had no cytotoxic effect on the cells and at higher concentrations, the extract showed mild toxicity resulting in the death of just 2.88% cells. Scratch assay showed 34.05%, 70.00%, 93.52% wound closure at 12hrs, 24hrs and 48hrs of incubation respectively. These results were similar compared to positive control which showed 37.60, 56.41 and 99.05% of wound closure. Further, flow cytometry-based studies revealed that the A. saccata leaf extract induced the expression of ECM remodelling factor collagen-1.

Conclusion

Our study revealed the wound healing capabilities of A. saccata In vitro. Hence, A. saccata could be recommended as a potential source of wound healing agents.

Sol-gel assisted fabrication of collagen hydrolysate composite scaffold: a novel therapeutic alternative to the traditional collagen scaffold

Collagen is one of the most widely used biomaterial for various biomedical applications. In this Research Article, we present a novel approach of using collagen hydrolysate, smaller fragments of collagen, as an alternative to traditionally used collagen scaffold. Collagen hydrolysate composite scaffold (CHCS) was fabricated with sol-gel transition procedure using tetraethoxysilane as the silica precursor. CHCS exhibits porous morphology with pore sizes varying between 380 and 780 μm. Incorporation of silica conferred CHCS with controlled biodegradation and better water uptake capacity. Notably, 3T3 fibroblast proliferation was seen to be significantly better under CHCS treatment when compared to treatment with collagen scaffold. Additionally, CHCS showed excellent antimicrobial activity against the wound pathogens Staphylococcus aureus, Bacillus subtilis, and Escherichia coli due to the inherited antimicrobial activity of collagen hydrolysate. In vivo wound healing experiments with full thickness excision wounds in rat model demonstrated that wounds treated with CHCS showed accelerated healing when compared to wounds treated with collagen scaffold. These findings indicate that the CHCS scaffold from collagen fragments would be an effective and affordable alternative to the traditionally used collagen structural biomaterials.

Bioengineered matrices--part 1: attaining structural success in biologic skin substitutes

Skin defect closure after injury or disease may present significant reconstructive challenges. Traditional epidermal coverage alone in the form of skin grafts often fall short in providing stable cover to restore structure and function of the skin. Excessive wound contraction and scar formation, particularly in defects of dermis and epidermis, may create functional and aesthetic problems. Progress in our understanding of molecular biology and tissue engineering have produced major advances in skin substitute technology, particularly relating to the dynamic cellular/extracellular matrix interaction that is critical to successful incorporation of a skin substitute. However, currently available skin substitutes still exhibit a range of problems including excessive wound contraction and scar formation, poor host tissue incorporation, revascularization and, in some cases, structural deficiencies in matrix design. The design principles and structural composition of the matrix must take into account collagenous forms, inherent resistance, porosity, and hydration. The ultimate matrix should be one that promotes intrinsic regeneration by encouraging cellular incorporation and cellular/extracellular cross communication. Attention to basic structural details rather than reliance on specialized cellular or peptide additions to the mix may well produce the advances we seek in improved incorporation of bioengineered skin substitutes.

Principles of wound care in patients with epidermolysis bullosa

Epidermolysis bullosa comprises a series of hereditary skin fragility disorders characterized by blister formation in response to minor friction or trauma. Acute and chronic wounds are part of the daily life of many epidermolysis bullosa patients. To offer proper care, health care providers need to understand the wound healing process, recognize the different types of wounds these patients may present, and be able to select among a wide variety of wound care products to optimize healing.