Use of ginsenoside Rg3-loaded electrospun PLGA fibrous membranes as wound cover induces healing and inhibits hypertrophic scar formation of the skin

Recent advances in nano and micro formulations of Ginsenoside to enhance their therapeutic efficacy

BACKGROUND AND AIMS

Ginsenosides, the main component of Panax ginseng, have long been recognized for their therapeutic benefits and are thought to have neuroprotective, antidiabetic, anti-depressant, antioxidant, anti-cancer, and anti-stress properties. However, due to their low water solubility, low biomembrane permeability, gastrointestinal dysfunction, and total metabolism in the body, ginsenosides have a poor absorption profile that has hindered the therapeutic potential of these organic molecules.

METHODS

Initially, we broadly illuminated the several techniques of extraction of Ginsenosides using Panax quinquefolius and Panax ginseng. Subsequently, we focused on different delivery methods to improve the stability, permeability, and solubility of natural chemicals, which raises the bioavailability of ginsenoside. Lastly, we explained significance of a variety of nano and microscale delivery systems, including liposomes, ethosomes, transfersomes, metal/metal oxide systems, micro/nanoemulsions, polymeric micro/nanoparticles (NPs), liposomes, transfersomes, and micelles to increase the bioavailability of ginsenosides.

RESULTS

The utilization of micro/nanoscale delivery methods, such as liposome-based delivery, polymer micro/nanoparticle distribution, and micro/nanoemulsion, to increase the bioavailability of ginsenosides has recently advanced, and we have emphasized these advances in this study. Furthermore, the disadvantages of ginsenosides were also discussed, including the challenges associated with putting these delivery systems into practice in clinical settings and suggestions for further research.

CONCLUSION

In summary, ginsenosides-based administration has several benefits that make it a potentially useful substance for a range of therapeutic purposes.

An Insight into Biodegradable Polymers and their Biomedical Applications for Wound Healing

Biodegradable polymers, encompassing both natural and synthetic polymers, have demonstrated efficacy as carriers for synthetic drugs, natural bioactive molecules, and inorganic metals. This is due to their ability to control the release of these substances. As a result, various advanced materials, such as nanoparticle- loaded hydrogels, nanofibrous scaffolds, and nanocomposites, have been developed. These materials have shown promise in enhancing processes, such as cell proliferation, vascular angiogenesis, hair growth, and wound healing management. Natural polymers, including hyaluronic acid, collagen, chitosan, gelatin, and alginate, as well as synthetic polymers like polylactic acid, polyglycolic acid, polylactic co-glycolic acid, and PCA, have significant potential for promoting wound healing. This study examines the advancements in biodegradable polymers for wound healing, specifically focusing on each polymer and its distinctive formulations. It also discusses the in vitro experiments conducted using different cell lines, as well as the in vivo studies that explore the numerous uses of these polymers in wound healing. The discussion also included the exploration of modifications or combinations of several polymers, as well as surface changes, in order to produce synergistic effects and address the limitations of individual polymers. The goal was to expedite the healing process of different chronic wounds. Due to this, there have been notable advancements in the technological use of polymeric mixes, including biodegradable polymer-based scaffolds, which have accelerated the process of wound healing.

Nanotechnology development in surgical applications: recent trends and developments

This paper gives a detailed analysis of nanotechnology's rising involvement in numerous surgical fields. We investigate the use of nanotechnology in orthopedic surgery, neurosurgery, plastic surgery, surgical oncology, heart surgery, vascular surgery, ophthalmic surgery, thoracic surgery, and minimally invasive surgery. The paper details how nanotechnology helps with arthroplasty, chondrogenesis, tissue regeneration, wound healing, and more. It also discusses the employment of nanomaterials in implant surfaces, bone grafting, and breast implants, among other things. The article also explores various nanotechnology uses, including stem cell-incorporated nano scaffolds, nano-surgery, hemostasis, nerve healing, nanorobots, and diagnostic applications. The ethical and safety implications of using nanotechnology in surgery are also addressed. The future possibilities of nanotechnology are investigated, pointing to a possible route for improved patient outcomes. The essay finishes with a comment on nanotechnology's transformational influence in surgical applications and its promise for future breakthroughs.

20(R)-ginsenoside Rg3-loaded polyurethane/marine polysaccharide based nanofiber dressings improved burn wound healing potentials

The management of deep burn injuries is extremely challenging, ascribed to their delayed wound healing rate, susceptibility for bacterial infections, pain, and increased risk of hypertrophic scarring. In our current investigation, a series of composite nanofiber dressings (NFDs) based on polyurethane (PU) and marine polysaccharides (i.e., hydroxypropyl trimethyl ammonium chloride chitosan, HACC and sodium alginate, SA) were accomplished by electrospinning and freeze-drying protocols. The 20(R)-ginsenoside Rg3 (Rg3) was further loaded into these NFDs to inhibit the formation of excessive wound scars. The PU/HACC/SA/Rg3 dressings showed a sandwich-like structure. The Rg3 was encapsulated in the middle layers of these NFDs and slowly released over 30 days. The PU/HACC/SA and PU/HACC/SA/Rg3 composite dressings demonstrated superior wound healing potentials over other NFDs. These dressings also displayed favorable cytocompatibility with keratinocytes and fibroblasts and could dramatically accelerate epidermal wound closure rate following 21 days of the treatment of a deep burn wound animal model. Interestingly, the PU/HACC/SA/Rg3 obviously reduced the excessive scar formation, with a collagen type I/III ratio closer to the normal skin. Overall, this study represented PU/HACC/SA/Rg3 as a promising multifunctional wound dressing, which promoted the regeneration of burn skins and attenuated scar formation.

Astragalus polysaccharides driven stretchable nanofibrous membrane wound dressing for joint wound healing

Joint wound dressings are currently significantly limited in their clinical applications due to their inferior mechanical properties and single therapeutic effect. Therefore, it is imperative to develop a versatile joint wound dressing that integrates adequate stretchability, desirable biocompatibility, and multiple biological effects into one system. We implemented the electrospinning technique in this study to fabricate a novel nanofibrous membrane (NFM) composed of gelatin (GEL) and astragalus polysaccharides (APS), termed GEL/APS NFM. The selection of GEL and APS confers excellent biocompatibility to GEL/APS NFM. Furthermore, the optimally proportioned GEL/APS NFM exhibits satisfactory stretchability and desirable wound healing efficiency. Furthermore, released APS can exert anti-inflammatory, procollagen deposition, and proangiogenic effects to accelerate epithelial tissue, enhancing joint wound healing. In summary, GEL/APS NFM offers a convenient and effective approach to promoting rapid joint wound healing, providing a novel approach to joint wound care.

Polymer-Based Wound Dressings Loaded with Ginsenoside Rg3

The skin, the largest organ in the human body, mainly plays a protective role. Once damaged, it can lead to acute or chronic wounds. Wound healing involves a series of complex physiological processes that require ideal wound dressings to promote it. The current wound dressings have characteristics such as high porosity and moderate water vapor permeability, but they are limited in antibacterial properties and cannot protect wounds from microbial infections, which can delay wound healing. In addition, several dressings contain antibiotics, which may have bad impacts on patients. Natural active substances have good biocompatibility; for example, ginsenoside Rg3 has anti-inflammatory, antibacterial, antioxidant, and other biological activities, which can effectively promote wound healing. Some researchers have developed various polymer wound dressings loaded with ginsenoside Rg3 that have good biocompatibility and can effectively promote wound healing and reduce scar formation. This article will focus on the application and mechanism of ginsenoside Rg3-loaded dressings in wounds.

Pentoxifylline/Chitosan Films on Wound Healing: In Vitro/In Vivo Evaluation

This study aimed to develop films of chitosan (CSF) associated with pentoxifylline (PTX) for healing cutaneous wounds. These films were prepared at two concentrations, F1 (2.0 mg/mL) and F2 (4.0 mg/mL), and the interactions between the materials, structural characteristics, in vitro release, and morphometric aspects of skin wounds in vivo were evaluated. The formation of the CSF film with acetic acid modifies the polymeric structure, and the PTX demonstrates interaction with the CSF, in a semi-crystalline structure, for all concentrations. The release for all films was proportional to the concentration, with two phases: a fast one of ≤2 h and a slow one of >2 h, releasing 82.72 and 88.46% of the drug after 72 h, being governed by the Fickian diffusion mechanism. The wounds of the mice demonstrate a reduction of up to 60% in the area on day 2 for F2 when compared to CSF, F1, and positive control, and this characteristic of faster healing speed for F2 continues until the ninth day with wound reduction of 85%, 82%, and 90% for CSF, F1, and F2, respectively. Therefore, the combination of CSF and PTX is effective in their formation and incorporation, demonstrating that a higher concentration of PTX accelerates skin-wound reduction.

EGCG inhibits hypertrophic scar formation in a rabbit ear model

OBJECTIVE

Hypertrophic scarring is a common skin fibro-proliferative disease, but currently there has no satisfactory drugs for anti-scar treatments. Previous study showed that epigallocatechin gallate (EGCG), the main catechin in green tea, improved wound healing and tissue fibrosis in both rats and mice. In the present study, the therapeutic effects of EGCG on hypertrophic scar were analyzed using a rabbit ear hypertrophic scar model.

MATERIALS

A rabbit ear model of hypertrophic scarring was used. DMSO, 0.5 mg EGCG/wound, 1.0 mg EGCG/wound or triamcinolone were injected subcutaneously once a week for 4 weeks. The scar elevation index (SEI) was measured using HE staining images, the collagen fibers were examined by Masson' trichrome staining images, and the number of capillaries in hypertrophic scar were calculated by CD31 staining images. The mRNA levels in the scar tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

Gross observation and histological evaluation showed the inhibitory effects of EGCG on hypertrophic scar formation at both doses, and decreased scar height and SEI were detected. EGCG also attenuated the mean collagen area fraction and decreased the number of capillaries in scar tissues. qRT-PCR revealed that EGCG significantly inhibited the mRNA expression of TGF-β1, Col I, Col III, α-SMA, and eNOS.

CONCLUSION

EGCG may serve as a useful candidate therapeutic drug for hypertrophic scar via inhibiting fibrotic gene expression and suppressing angiogenesis.

Ginsenoside Rg3 enhances the radiosensitivity of lung cancer A549 and H1299 cells via the PI3K/AKT signaling pathway

Lung cancer is one of the most common cancers and the leading cause of cancer-related deaths in the world. Radiation is widely used for the treatment of lung cancer. However, radioresistance and toxicity limit its effectiveness. Ginsenoside Rg3 (Rg3) is a positive monomer extracted from ginseng and has been shown to the anti-cancer ability on many tumors. The aim of the present study was to ascertain whether Rg3 is able to enhance the radiosensitivity of lung cancer cells and investigate the underlying mechanisms. The effect of Rg3 on cell proliferation was examined by Cell Counting Kit-8 (CCK-8) and radiosensitivity was measured by colony formation assay. Flow cytometry, transwell, and wound healing assay were used to determine apoptosis, cell cycle, and metastasis. Western blot was used to detect the main protein levels of the PI3K/AKT signaling pathway. We found that Rg3 inhibited cell proliferation, promoted apoptosis, and suppressed migration and invasion in radio-induced lung cancer cells. In addition, Rg3 increased the proportion of G2/M phase cells and inhibited the formation of cell colonies. Moreover, Rg3 decreased the expression levels of PI3K, p-AKT, and PDK1 in radio-induced cells. These findings indicate that Rg3 may be able to enhance the radiosensitivity in lung cancer cells by the PI3K/AKT signaling pathway. These results demonstrate the therapeutic potential of Rg3 as a radiosensitizer for lung cancer.

Micron and nano hybrid ufasomes from conjugated linoleic acid, their vesiculation and encapsulation of ginsenoside Rg3

BACKGROUND

Unsaturated fatty acids used to form unstable micro-vesicles, while conjugate linoleic acid (CLA)-sodium dodecyl sulfate (SDS) can self-assembly to stable nano-conjugate linoleic acid vesicles (nano-CLAVs). Generally, micro-capsule could geometrically provide higher loading capacity but also generate concerns in construction convenience, sustained release, bioaccessibility and stability. Hence there is a contradiction between loading capacity and encapsulation efficiency. Therefore, the study of the factors that decide the capsule size falling in nano or micron size with same capsule material would be a benefit to food or drug delivery science.

RESULTS

The micron- and nano-CLAVs were constructed for encapsulation and sustained release of ginsenoside Rg3. The formation mechanism of nano or micron capsule,s the effect of vesicle sizes on encapsulation efficiency, drug loading efficiency and stability of the encapsulated Rg3 were investigated. It was found that with the addition of salt (PBS), the size of CLAVs jumped from nano to micron. Furthermore, the salt concentration is the key factor that decides the vesicle size of nano or micron. The pH at fabrication triggers the vesiculation and dramatically affects the vesicle size over the nano and micron scales.

CONCLUSION

Compared to the nano-CLAVs, micron vesicles enhanced the loading capacity to 137.6% and the encapsulation efficiency to 138.4%, respectively. Meanwhile, the micron-CLAVs performed similar sustained release of Rg3 as the nano-CLAVs did, and was stable for 120 days at room temperature or sustained 98.9% of capsules after centrifuge at 6090 × g for 20 min. © 2022 Society of Chemical Industry.

Preparation and pharmacological effects of minor ginsenoside nanoparticles: a review

Ginseng (Panax ginseng) is a perennial herbaceous plant belonging to Panax genus of Araliaceae. Ginsenosides are a kind of important compounds in ginseng and minor ginsenosides are secondary metabolic derivatives of ginsenosides. Studies have shown that minor ginsenosides have many pharmacological effects, such as antioxidant, anti-tumor, anti-platelet aggregation, and neuroprotective effects. However, the therapeutic effects of minor ginsenosides are limited due to poor solubility in water, short half-life, and poor targeting accuracy. In recent years, to improve the application efficiency, the research on the nanocrystallization of minor ginsenosides have attracted extensive attention from researchers. This review focuses on the classification, preparation methods, pharmacological effects, and action mechanisms of minor ginsenoside nanoparticles, as well as existing problems and future direction of relevant research, which provides a reference for the in-depth research of minor ginsenoside nanoparticles.

Poloxamer 407 and Hyaluronic Acid Thermosensitive Hydrogel-Encapsulated Ginsenoside Rg3 to Promote Skin Wound Healing

Ginsenoside Rg3 has shown beneficial effects in various skin diseases. The current interest in designing and developing hydrogels for biomedical applications continues to grow, inspiring the further development of drug-loaded hydrogels for tissue repair and localized drug delivery. The aim of the present study was to develop an effective and safe hydrogel (Rg3-Gel), using ginsenoside Rg3, and we evaluated the wound-healing potential and therapeutic mechanism of Rg3-Gel. The results indicated that the optimized Rg3-Gel underwent discontinuous phase transition at low and high temperatures. Rg3-Gel also exhibited good network structures, swelling water retention capacity, sustainable release performance, and excellent biocompatibility. Subsequently, the good antibacterial and antioxidant properties of Rg3-Gel were confirmed by in vitro tests. In full-thickness skin defect wounded models, Rg3-Gel significantly accelerated the wound contraction, promoted epithelial and tissue regeneration, and promoted collagen deposition and angiogenesis. In addition, Rg3-Gel increased the expression of autophagy proteins by inhibiting the MAPK and NF-KB pathways in vivo. It simultaneously regulated host immunity by increasing the abundance of beneficial bacteria and the diversity of the wound surface flora. From these preliminary evaluations, it is possible to conclude that Rg3-Gel has excellent application potential in wound-healing drug delivery systems.

Efficacy of ginsenoside Rg3 nanoparticles against Ehrlich solid tumor growth in mice

Solid tumors are fairly common and face many clinical difficulties since they are hardly surgically resectable and broadly do not respond to radiation and chemotherapy. The current study aimed to fabricate ginsenoside Rg3 nanoparticles (Rg3-NPs) and evaluate their antitumor effect against Ehrlich solid tumors (EST) in mice. Rg3-NPs were fabricated using whey protein isolates (WPI), maltodextrin (MD), and gum Arabic (GA). EST was developed by the injection of mice with Ehrlich ascites cells (2.5 × 10⁶). The mice were divided into a control group, EST group, and the EST groups that were treated orally 2 weeks for with normal Rg3 (3 mg/kg b.w.), Rg3-NPs at a low dose (3 mg/kg b.w.), and Rg3-NPs at a high dose (6 mg/kg b.w.). Serum and solid tumors were collected for different assays. The results revealed that synthesized Rg3-NPs showed a spherical shape with an average particle size of 20 nm and zeta potential of -5.58 mV. The in vivo study revealed that EST mice showed a significant increase in AFP, Casp3, TNF-α, MMP-9, VEGF, MDA, and DNA damage accompanied by a significant decrease in SOD and GPx. Treatment with Rg3 or Rg3-NPs decreased the tumor weight and size and induced a significant improvement in all the biochemical parameters. Rg3-NPs were more effective than Rg3, and the improvement was dose-dependent. It could be concluded that fabrication of Rg3-NPs enhanced the protective effect against EST development which may be due to the synergistic effect of Rg3 and MD, GA, and WPI.

A Review of Hypertrophic Scar and Keloid Treatment and Prevention in the Pediatric Population: Where Are We Now?

Significance: This body of work gives a concise and comprehensive overview for the clinician and scientist on the latest treatment modalities for hypertrophic scars (HTS) and keloids in the pediatric population, as well as the most promising methods of prevention currently being investigated. This review will serve as a guide to the clinician for treatment selection and as an efficient tool for the scientist to achieve a comprehensive overview of the scientific literature to guide their future experiments aimed at pathologic scar prevention. Recent Advances: Current studies in the literature suggest carbon dioxide (CO₂) laser and E-light (bipolar radiofrequency, intense pulsed light, and cooling) are two of the most effective treatment modalities for HTS, while surgical excision+CO₂ laser+triamcinolone injection was one of the most successful treatments for keloids. In animal models, drug impregnated electrospun nanofiber dressings offer encouraging results for HTS prevention, while Kelulut honey showed promising results for keloid prevention. Critical Issues: Treatment outcome reproducibility is hindered by small cohorts of patients, inadequate-follow up, and variability in assessment tools. Prevention studies show multiple ways of achieving the same result, yet fall short of complete prevention. Furthermore, some studies that have purported full prevention have not been validated. Future Directions: To establish a standard of care, large clinical trials of the most successful modalities in small cohorts are needed. The key for prevention will be validation in animal models of the most successful methods, followed by translational and clinical studies.

In vitro and in vivo biological assessment of dual drug-loaded coaxial nanofibers for the treatment of corneal abrasion

The treatment of corneal abrasion currently involves the topical administration of antibiotics, with moxifloxacin HCl (0.5% w/v) eye drops being one of the most widely used treatments. Our previous work (Tawfik et al., 2020) involved the development of coaxial poly-lactic-co-glycolic acid (PLGA) and polyvinylpyrrolidone (PVP) nanofibers loaded with the antibiotic moxifloxacin HCl and the anti-scarring agent pirfenidone in the core (PVP) and shell (PLGA) respectively, with a view to the system comprising an ocular insert for the combination therapy of corneal abrasion. In this study, we examine the antimicrobial, anti-scarring and pharmacokinetic properties of the fibers alongside consideration of their toxicity and propensity for irritation. Minimum inhibitory concentration and zone of inhibition studies against S. aureus and P. aeruginosa were performed, while fibroblast cell viability and α-smooth muscle actin (α-SMA, a biomarker for scar formation) were measured using MTT and Western Blot assays, respectively. Pharmacokinetic studies and efficacy against infection were performed using a rabbit model, while ocular irritancy was assessed using the Draize test. The studies demonstrated that the antimicrobial activity of the moxifloxacin HCl was preserved following encapsulation into the nanofibers, while the downregulation of α-SMA was demonstrated using concentrations below the IC₂₀ values (concentration required to decrease corneal fibroblast viability by no more than 20%). The pharmacokinetic study showed retention and sustained release of the moxifloxacin HCl over a 24-hour period, in contrast to equivalent eye drops which required four times daily dosing. Evidence of low level (according to the MMTS scale) irritation was detected for the nanofiber systems. Overall, the study has demonstrated that the dual drug-loaded nanofiber system shows potential for once daily dosing as an ocular insert for the treatment of corneal abrasion.

Pre-Emptive Priming of Human Skin Improves Cutaneous Scarring and Is Superior to Immediate and Delayed Topical Anti-Scarring Treatment Post-Wounding: A Double-Blind Randomised Placebo-Controlled Clinical Trial

The concept of pre-emptive priming of skin pre-surgery offers a novel approach in optimizing cutaneous scarring outcome. We previously showed an anti-scarring topical (epigallocatechin-3-gallate (EGCG)) is effective in improving skin scarring when applied post-surgery. The objective was to deliver an active compound at the optimal time in order to maximize its impact and improve cutaneous scarring. Therefore, pre-emptive application of anti-scarring topical pre-surgery compared with post-surgery can potentially be superior on scarring outcome. This double-blinded randomized placebo-controlled trial compares the effects of pre-emptive priming of skin with an anti-scarring topical pre-surgery versus post-surgery. Healthy volunteers (n = 40) were split into 4-groups; each undergoing different modes of application versus placebo: Group-1 = priming (7Days) pre-injury, Group-2 = priming (3D) pre-injury, Group-3 = immediate (0D) day-of-injury, Group-4 = delayed application (14D) post-injury. Excisional skin-biopsies in upper-arms were evaluated weekly with multiple quantitative devices over 8-weeks. Histological, immunohistochemical, mRNA sequencing and QRT-PCR studies were performed on tissue-biopsies. EGCG reduced mast cells at weeks-4 and 8 by gene and protein analyses (p < 0.01). Group 1 was superior to other groups (p < 0.01) in both clinical (blood flow) and laboratory parameters (elastin and immune marker expression). Additionally, there was down-regulation of angiogenic-markers by mRNA-sequencing and of CD31 and VEGF-A at weeks-4 and 8 (p < 0.01) by immunohistochemistry and at week-4 (p < 0.05) by QRT-PCR. EGCG increased antioxidant levels (HO-1) at week-4 (p < 0.01) plus elastin at week-8 (p < 0.01). In conclusion, pre-emptive priming of skin pre-injury has significant beneficial effects on surgically induced skin scarring shown by reducing mast cells, blood flow and angiogenesis plus increasing elastin content. This clinical trial was registered with ISRCTN (ISRCTN70155584).

Pre-Emptive Priming of Human Skin Improves Cutaneous Scarring and Is Superior to Immediate and Delayed Topical Anti-Scarring Treatment Post-Wounding: A Double-Blind Randomised Placebo-Controlled Clinical Trial

The concept of pre-emptive priming of skin pre-surgery offers a novel approach in optimizing cutaneous scarring outcome. We previously showed an anti-scarring topical (epigallocatechin-3-gallate (EGCG)) is effective in improving skin scarring when applied post-surgery. The objective was to deliver an active compound at the optimal time in order to maximize its impact and improve cutaneous scarring. Therefore, pre-emptive application of anti-scarring topical pre-surgery compared with post-surgery can potentially be superior on scarring outcome. This double-blinded randomized placebo-controlled trial compares the effects of pre-emptive priming of skin with an anti-scarring topical pre-surgery versus post-surgery. Healthy volunteers (n = 40) were split into 4-groups; each undergoing different modes of application versus placebo: Group-1 = priming (7Days) pre-injury, Group-2 = priming (3D) pre-injury, Group-3 = immediate (0D) day-of-injury, Group-4 = delayed application (14D) post-injury. Excisional skin-biopsies in upper-arms were evaluated weekly with multiple quantitative devices over 8-weeks. Histological, immunohistochemical, mRNA sequencing and QRT-PCR studies were performed on tissue-biopsies. EGCG reduced mast cells at weeks-4 and 8 by gene and protein analyses (p < 0.01). Group 1 was superior to other groups (p < 0.01) in both clinical (blood flow) and laboratory parameters (elastin and immune marker expression). Additionally, there was down-regulation of angiogenic-markers by mRNA-sequencing and of CD31 and VEGF-A at weeks-4 and 8 (p < 0.01) by immunohistochemistry and at week-4 (p < 0.05) by QRT-PCR. EGCG increased antioxidant levels (HO-1) at week-4 (p < 0.01) plus elastin at week-8 (p < 0.01). In conclusion, pre-emptive priming of skin pre-injury has significant beneficial effects on surgically induced skin scarring shown by reducing mast cells, blood flow and angiogenesis plus increasing elastin content. This clinical trial was registered with ISRCTN (ISRCTN70155584).

Tetracyclic and Pentacyclic Triterpenes with High Therapeutic Efficiency in Wound Healing Approaches

Wounds are among the most common skin conditions, displaying a large etiological diversity and being characterized by different degrees of severity. Wound healing is a complex process that involves multiple steps such as inflammation, proliferation and maturation and ends with scar formation. Since ancient times, a widely used option for treating skin wounds are plant- based treatments which currently have become the subject of modern pharmaceutical formulations. Triterpenes with tetracyclic and pentacyclic structure are extensively studied for their implication in wound healing as well as to determine their molecular mechanisms of action. The current review aims to summarize the main results of in vitro, in vivo and clinical studies conducted on lupane, ursane, oleanane, dammarane, lanostane and cycloartane type triterpenes as potential wound healing treatments.

Ginsenosides: potential therapeutic source for fibrosis-associated human diseases

Tissue fibrosis is an eventual pathologic change of numerous chronic illnesses, which is characterized by resident fibroblasts differentiation into myofibroblasts during inflammation, coupled with excessive extracellular matrix deposition in tissues, ultimately leading to failure of normal organ function. Now, there are many mechanistic insights into the pathogenesis of tissue fibrosis, which facilitate the discovery of effective antifibrotic drugs. Moreover, many chronic diseases remain a significant clinical unmet need. For the past five years, many research works have undoubtedly addressed the functional dependency of ginsenosides in different types of fibrosis and the successful remission in various animal models treated with ginsenosides. Caveolin-1, interleukin, thrombospondin-1 (TSP-1), liver X receptors (LXRs), Nrf2, microRNA-27b, PPARδ-STAT3, liver kinase B1 (LKB1)-AMPK, and TGF-β1/Smads are potential therapy targeting using ginsenosides. Ginsenosides can play a targeting role and suppress chronic inflammatory response, collagen deposition, and epithelial-mesenchymal transition (EMT), as well as myofibroblast activation to attenuate fibrosis. In this report, our aim was to focus on the therapeutic prospects of ginsenosides in fibrosis-related human diseases making use of results acquired from various animal models. These findings should provide important therapeutic clues and strategies for the exploration of new drugs for fibrosis treatment.

Bionic Poly(γ-Glutamic Acid) Electrospun Fibrous Scaffolds for Preventing Hypertrophic Scars

Hypertrophic scarring (HS) remains a great challenge in wound dressing. Although various bionic extracellular matrix (ECM) biomaterials have been designed towards HS treatment, not all biomaterials can synergize biological functions and application functions in wound repair. Bionic scar-inhibiting scaffolds, loaded with biomolecules or drugs, become promising strategies for scarless skin regeneration. In this work, inspired by the physicochemical environment of ECM, a versatile fabrication of poly(γ-glutamic acid) based on electrospun photocrosslinkable hydrogel fibrous scaffolds incorporated with ginsenoside Rg3 (GS-Rg3) is developed for tissue repair and wound therapy. Decorated with adhesive peptide, bionic fibrous scaffolds can accelerate fibroblasts to sprout and grow, forming organized space-filling basement that gradually fills a depression before wound close up in the early stage. Additionally, by sustained release of GS-Rg3 in late stage, fibrous scaffolds promote scarless wound healing in vivo as evidenced by the promotion of cell communication and skin regeneration, as well as the subsequent decrease of angiogenesis and collagen accumulation. These ECM-inspired fibrous scaffolds, therefore, offer new perspectives on accelerated wound healing and tissue regeneration.

Self-Nanoemulsifying Electrospun Fiber Enhancing Drug Permeation

Electrospun fibers are excellent drug carriers and tissue engineering scaffolds. However, approaches to promote drug permeation in tissues with such carriers remain of great interest. Here, we propose a Quality-by-Design strategy to enhance drug permeation with self-nanoemulsifying electrospun fibers. Owing to the nanoemulsion which formed spontaneously when the polymer contacts aqueous solution such as body fluid, the resulting drug-laden fibrous membrane exhibits an outstanding drug permeation and therapeutic enhancement effect in a Franz cell experiment with ex vivo abdomen skin of rats, an artificial connective tissue model, and an in vivo rheumatoid arthritis model in rats. Meanwhile, the material also shows the capacity of rational regulation on the rate of drug release. These features of the present strategy establish our material as a new efficient approach for various clinical conditions calling for cure.

Therapeutic effects of a liquid bandage prepared with cellulose powders from Styela clava tunics and Broussonetia kazinoki bark: Healing of surgical wounds on the skin of Sprague Dawley rats

Cellulose in different forms has extensively been applied in biomedical treatments, including scaffolding, tissue engineering and tissue formation. To evaluate the therapeutic effects of a liquid bandage (LB) prepared with cellulose powders from Styela clava tunics (SCT) and Broussonetia kazinoki bark (BSLB) for healing cutaneous wounds, the remedial effects of a low concentration (LoBSLB) and a high concentration (HiBSLB) of BSLB on skin regeneration and toxicity in Sprague Dawley rats. Results indicated that the total area of skin involved in the surgical wound was lower in the BSLB-treated group compared with the Vehicle-treated group at days 4–12, although some variations were observed in the HiBSLB-treated group. In addition, the BSLB-treated group showed significantly enhanced width of the re-epithelialization region and epidermal thickness when compared with the Vehicle-treated group. Furthermore, significant stimulation in the expression level of collagen-1 and the signaling pathway of VEGF after topical application of BSLB was indicated. No liver or kidney toxicities were detected for either doses of BSLB. Overall, the results of the present study suggest that BSLB accelerates the process of wound healing in surgical skin wounds of Sprague Dawley rats through stimulation of re-epithelialization and connective tissue formation, without any accompanying significant toxicity.

PLGA based drug delivery systems: Promising carriers for wound healing activity

Wound treatment remains one of the most prevalent and economically burdensome healthcare issues in the world. Current treatment options are limited and require repeated administrations which led to the development of new therapeutics to satisfy the unmet clinical needs. Many potent wound healing agents were discovered but most of them are fragile and/or sensitive to in vivo conditions. Poly(lactic-co-glycolic acid) (PLGA) is a widely used biodegradable polymer approved by food and drug administration and European medicines agency as an excipient for parenteral administrations. It is a well-established drug delivery system in various medical applications. The aim of the current review is to elaborate the applications of PLGA based drug delivery systems carrying different wound healing agents and also present PLGA itself as a wound healing promoter. PLGA carriers encapsulating drugs such as antibiotics, anti-inflammatory drugs, proteins/peptides, and nucleic acids targeting various phases/signaling cycles of wound healing, are discussed with examples. The combined therapeutic effects of PLGA and a loaded drug on wound healing are also mentioned.

Ginsenoside Rg3 micelles mitigate doxorubicin-induced cardiotoxicity and enhance its anticancer efficacy

Doxorubicin (DOX) is one of the most effective chemotherapy agents used in the treatment of hematological and solid tumors, however, it causes dose-related cardiotoxicity that may lead to heart failure in patients. One of the major reasons was increased reactive oxygen species (ROS) production. Ginsenoside Rg3 (Rg3), was powerful free radical scavengers and possessed cardioprotective effects. Nevertheless, Rg3 has low aqueous solubility and oral bioavailability, limiting its effects. Herein, we encapsulated Rg3 through spontaneous self-assembly of Pluronic F127 to improve its solubility and oral bioavailability. Moreover, co-administering Rg3 in Pluronic F127 micelles with doxorubicin can mitigate the cardiotoxicity, with ameliorating mitochondrial and metabolic function, improving calcium handling, and decreasing ROS production. In addition, it can improve the anticancer efficacy of doxorubicin. Therefore, our study provides a rational strategy for further developing a potentially viable adjunct-supportive treatment for reducing toxicity and increasing efficiency on chemotherapy.

Functional electrospun fibers for the treatment of human skin wounds

Wounds are trauma induced defects of the human skin involving a multitude of endogenous biochemical events and cellular reactions of the immune system. The healing process is extremely complex and affected by the patient's physiological conditions, potential implications like infectious pathogens and inflammation as well as external factors. Due to increasing incidence of chronic wounds and proceeding resistance of infection pathogens, there is a strong need for effective therapeutic wound care. In this context, electrospun fibers with diameters in the nano- to micrometer range gain increasing interest. While resembling the structure of the native human extracellular matrix, such fiber mats provide physical and mechanical protection (including protection against bacterial invasion). At the same time, the fibers allow for gas exchange and prevent occlusion of the wound bed, thus facilitating wound healing. In addition, drugs can be incorporated within such fiber mats and their release can be adjusted by the material and dimensions of the individual fibers. The review gives a comprehensive overview about the current state of electrospun fibers for therapeutic application on skin wounds. Different materials as well as fabrication techniques are introduced including approaches for incorporation of drugs into or drug attachment onto the fiber surface. Against the background of wound pathophysiology and established therapy approaches, the therapeutic potential of electrospun fiber systems is discussed. A specific focus is set on interactions of fibers with skin cells/tissues as well as wound pathogens and strategies to modify and control them as key aspects for developing effective wound therapeutics. Further, advantages and limitations of controlled drug delivery from fiber mats to skin wounds are discussed and a future perspective is provided.

BMP‑7 suppresses excessive scar formation by activating the BMP‑7/Smad1/5/8 signaling pathway

Scarring is the inevitable consequence of wound repair, which may cause significant physical and mental pain to patients when excessive. Bone morphogenetic protein-7 (BMP-7) has been proved to inhibit TGF-β-induced fibrosis in various tissues including dermal papilla cells. However, the effect of BMP-7 on hypertrophic scarring, a common proliferative disorder of dermal fibroblasts, has not been determined. To overcome this problem, the present study established a mouse model of thermal injury to investigate the inhibitory effects of BMP-7 on scar formation. The histological analysis of scar tissues was performed by H&E and Masson's trichrome staining. Western blot assay was used to determine the level changes of related proteins and TUNEL assay was performed to assess the apoptosis of scar tissues. The results demonstrated that BMP-7 promoted wound healing and inhibited scar formation when compared with untreated mice. Collagen deposition and the expression of fibrotic proteins were suppressed in the scar tissues of mice treated with BMP-7. In addition, BMP-7 induced fibroblast apoptosis in scar tissues. Furthermore, activation of the BMP-7/Smad1/5/8 signaling pathway may have been involved in the inhibitory effects of BMP-7 on scar formation. In conclusion, the results of the present study indicate that BMP-7 may inhibit excessive scar formation via activation of the BMP-7/Smad1/5/8 signaling pathway. The results present a potential alternative therapeutic strategy for the treatment of hypertrophic scarring.

Biomaterials and tissue engineering for scar management in wound care

Scars are a natural and unavoidable result from most wound repair procedures and the body's physiological healing response. However, they scars can cause considerable functional impairment and emotional and social distress. There are different forms of treatments that have been adopted to manage or eliminate scar formation. This review covers the latest research in the past decade on using either natural agents or synthetic biomaterials in treatments for scar reduction.

Electrospray biodegradable microcapsules loaded with curcumin for drug delivery systems with high bioactivity

Biodegradable microcapsules as novel drug delivery systems were successfully fabricated by one-step processing using an electrospray technique.

Quickly promoting angiogenesis by using a DFO-loaded photo-crosslinked gelatin hydrogel for diabetic skin regeneration

A desferrioxamine (DFO)-loaded photo-crosslinked gelatin hydrogel was used to reconstruct vessel network and prompt skin regeneration in diabetic wounds.

Two-dimensional electrospun nanofibrous membranes for promoting random skin flap survival

Electrospun fibrous membranes made of natural materials are more advantageous for random skin flap survival, and can be used as carrier implantation materials for improving skin flap survival rate.

Astragulus polysaccharide-loaded fibrous mats promote the restoration of microcirculation in/around skin wounds to accelerate wound healing in a diabetic rat model

Tissue engineering scaffolds (TES) can carry numerous biomacromolecules and cells, and they have been widely used in diabetic skin wound healing with positive effects. However, the bioactive retention of biomacromolecules and cells during fabrication and storage is still a factor restricting their use. Moreover, impaired blood supply in/around poorly healing diabetic skin wounds has not been considered. In the present study, a bioactive natural substance of Astragalus polysaccharide (APS), which has stable and confirmed effects on endothelial protection, was embedded into fibrous TES by electrospinning. The administration of APS-loaded TES on the skin wound in a diabetic rat model led to a dose-dependent promotion in skin blood flow around wounds and an increase in endoglin expression and microvessel density in regenerated skin tissues. Furthermore, the higher loading of APS in TES led to faster collagen synthesis, appendage and epidermal differentiation, and wound closure. In summary, the combination of APS with TES is a potentially novel therapeutic strategy for diabetic skin wound healing, as it not only mimics the ultrastructure of extracellular matrixes but also restores skin microcirculation.

Smart Dressings Based on Nanostructured Fibers Containing Natural Origin Antimicrobial, Anti-Inflammatory, and Regenerative Compounds

A fast and effective wound healing process would substantially decrease medical costs, wound care supplies, and hospitalization significantly improving the patients' quality of life. The search for effective therapeutic approaches seems to be imperative in order to avoid the aggravation of chronic wounds. In spite of all the efforts that have been made during the recent years towards the development of artificial wound dressings, none of the currently available options combine all the requirements necessary for quick and optimal cutaneous regeneration. Therefore, technological advances in the area of temporary and permanent smart dressings for wound care are required. The development of nanoscience and nanotechnology can improve the materials and designs used in topical wound care in order to efficiently release antimicrobial, anti-inflammatory and regenerative compounds speeding up the endogenous healing process. Nanostructured dressings can overcome the limitations of the current coverings and, separately, natural origin components can also overcome the drawbacks of current antibiotics and antiseptics (mainly cytotoxicity, antibiotic resistance, and allergies). The combination of natural origin components with demonstrated antibiotic, regenerative, or anti-inflammatory properties together with nanostructured materials is a promising approach to fulfil all the requirements needed for the next generation of bioactive wound dressings. Microbially compromised wounds have been treated with different essential oils, honey, cationic peptides, aloe vera, plant extracts, and other natural origin occurring antimicrobial, anti-inflammatory, and regenerative components but the available evidence is limited and insufficient to be able to draw reliable conclusions and to extrapolate those findings to the clinical practice. The evidence and some promising preliminary results indicate that future comparative studies are justified but instead of talking about the beneficial or inert effects of those natural origin occurring materials, the scientific community leads towards the identification of the main active components involved and their mechanism of action during the corresponding healing, antimicrobial, or regenerative processes and in carrying out systematic and comparative controlled tests. Once those natural origin components have been identified and their efficacy validated through solid clinical trials, their combination within nanostructured dressings can open up new avenues in the fabrication of bioactive dressings with outstanding characteristics for wound care. The motivation of this work is to analyze the state of the art in the use of different essential oils, honey, cationic peptides, aloe vera, plant extracts, and other natural origin occurring materials as antimicrobial, anti-inflammatory and regenerative components with the aim of clarifying their potential clinical use in bioactive dressings. We conclude that, for those natural occurring materials, more clinical trials are needed to reach a sufficient level of evidence as therapeutic agents for wound healing management.

Advances in skin regeneration: application of electrospun scaffolds

The paucity of cellular and molecular signals essential for normal wound healing makes severe dermatological ulcers stubborn to heal. The novel strategies of skin regenerative treatments are focused on the development of biologically responsive scaffolds accompanied by cells and multiple biomolecules resembling structural and biochemical cues of the natural extracellular matrix (ECM). Electrospun nanofibrous scaffolds provide similar architecture to the ECM leading to enhancement of cell adhesion, proliferation, migration and neo tissue formation. This Review surveys the application of biocompatible natural, synthetic and composite polymers to fabricate electrospun scaffolds as skin substitutes and wound dressings. Furthermore, the application of biomolecules and therapeutic agents in the nanofibrous scaffolds viz growth factors, genes, antibiotics, silver nanoparticles, and natural medicines with the aim of ameliorating cellular behavior, wound healing, and skin regeneration are discussed.