The effects of artocarpin on wound healing: in vitro and in vivo studies

Synthesis of novel bioadhesive hydrogels via facile Thiol-Ene click chemistry for wound healing applications

Development of outstanding, cost-effective and elastic hydrogels as bioadhesive using Thiol-Ene click chemistry was verified. The visible light photocrosslinkable hydrogels composed of methacrylated chitosan/2,2'-(Ethylenedioxy) diethanethiol formed in presence of eosin-Y photoinitiator. Such hydrogels hold great promise for wound healing applications due to their tunable properties. Main components of hydrogels were extensively characterized using spectroscopic techniques for chemical analysis, thermal analysis, and topologic nanostructure. Various optimization conditions for best gelation time were investigated. Mechanical properties of tensile strength and elongation at break (%) were verified for best wound healing applications. Optimum hydrogel was subjected to for cytotoxicity and microbial suppression evaluation and in-vivo wound healing test for efficient wound healing evaluations. Our results demonstrate the potential use of injectable hydrogels as valuable bioadhesives in bioengineering and biomedical applications, particularly in wound closure and patches.

A critical overview of challenging roles of medicinal plants in improvement of wound healing technology

PURPOSE

Chronic diseases often hinder the natural healing process, making wound infections a prevalent clinical concern. In severe cases, complications can arise, potentially leading to fatal outcomes. While allopathic treatments offer numerous options for wound repair and management, the enduring popularity of herbal medications may be attributed to their perceived minimal side effects. Hence, this review aims to investigate the potential of herbal remedies in efficiently treating wounds, presenting a promising alternative for consideration.

METHODS

A literature search was done including research, reviews, systematic literature review, meta-analysis, and clinical trials considered. Search engines such as Pubmed, Google Scholar, and Scopus were used while retrieving data. Keywords like Wound healing 'Wound healing and herbal combinations', 'Herbal wound dressing', Nanotechnology and Wound dressing were used.

RESULT

This review provides valuable insights into the role of natural products and technology-based formulations in the treatment of wound infections. It evaluates the use of herbal remedies as an effective approach. Various active principles from herbs, categorized as flavonoids, glycosides, saponins, and phenolic compounds, have shown effectiveness in promoting wound closure. A multitude of herbal remedies have demonstrated significant efficacy in wound management, offering an additional avenue for care. The review encompasses a total of 72 studies, involving 127 distinct herbs (excluding any common herbs shared between studies), primarily belonging to the families Asteraceae, Fabaceae, and Apiaceae. In research, rat models were predominantly utilized to assess wound healing activities. Furthermore, advancements in herbal-based formulations using nanotechnology-based wound dressing materials, such as nanofibers, nanoemulsions, nanofiber mats, polymeric fibers, and hydrogel-based microneedles, are underway. These innovations aim to enhance targeted drug delivery and expedite recovery. Several clinical-based experimental studies have already been documented, evaluating the efficacy of various natural products for wound care and management. This signifies a promising direction in the field of wound treatment.

CONCLUSION

In recent years, scientists have increasingly utilized evidence-based medicine and advanced scientific techniques to validate the efficacy of herbal medicines and delve into the underlying mechanisms of their actions. However, there remains a critical need for further research to thoroughly understand how isolated chemicals extracted from herbs contribute to the healing process of intricate wounds, which may have life-threatening consequences. This ongoing research endeavor holds great promise in not only advancing our understanding but also in the development of innovative formulations that expedite the recovery process.

Extracellular vesicles derived from human foreskin cells (hFS-Exo) accelerate cell migration and angiogenesis through MAPK pathway: an in vitro study

BACKGROUND

Wound healing is one of the important processes in the body. Attempts to create new drugs are of interest due to the side effects of natural and chemical wound healing compounds. To overcome this obstacle, stem cells have been used as healing agents. However, both difficulties in collection and risks such as rejection and teratoma in the recipient body have limited the use of stem cells, directly. Since the potential content of the stem cells can be transferred to the recipient cells by vesicles, small extracellular vesicles have recently become prominent agents.

METHODS AND RESULTS

The wound-healing effect of extracellular vesicles derived from foreskin cells was investigated in both keratinocyte and endothelial cells. Migration assay, RT-PCR, Col1a1 ELISA and Western Blot experiments were utilized to reveal healing effect of EVs and its possible molecular pathways. EV-treated groups exhibited more proliferative, invasive, and migrative characteristics. When comparing to the control group, new vessel formation was induced in EV groups. An increase in gene levels of growth factors related to wound healing and change in the mitogen-activated protein kinase (MAPK) signaling pathway proteins in EV-treated groups were determined. Possible molecular mechanisms underlying cell movements were associated with the MAPK pathway. It was found that human foreskin cell EVs (hFS-Exo) may have a potential to heal wounds in a short period of time by triggering the MAPK pathway.

CONCLUSIONS

hFS-Exo could be a new promising wound healing agent in the future.

Multilayer PVA/gelatin nanofibrous scaffolds incorporated with Tanacetum polycephalum essential oil and amoxicillin for skin tissue engineering application

Wound infection is still an important challenge in healing of different types of skin injuries. This highlights the need for new and improved antibacterial agents with novel and different mechanisms of action. In this study, by electrospinning process Tanacetum polycephalum essential oil (EO), as a natural antibacterial and anti-inflammatory agent, along with Amoxicillin (AMX) as an antibiotic are incorporated into PVA/gelatin-based nanofiber mats individually and in combination to fabricate a novel wound dressing. Briefly, we fabricated PVA/gelatin loaded by Amoxicillin as first layer for direct contact with wound surface to protects the wound from exogenous bacteria, and then built a PVA/gelatin/Tanacetum polycephalum essential oil layer on the first layer to help cleanses the wound from infection and accelerates wound closure. Finally, PVA/gelatin layer as third layer fabricated on middle layer to guarantee desirable mechanical properties. For each layer, the electrospinning parameters were adjusted to form bead-free fibers. The morphology of fabricated nanofiber scaffolds was characterized by Fourier-transform infrared (FTIR) and scanning electron microscopy (SEM). Microscopic images demonstrated the smooth bead-free microstructures fabrication of every layer of nanofiber with a uniform fiber size of 126.888 to 136.833 nm. While, EO and AMX increased the diameter of nanofibers but there was no change in physical structure of nanofiber. The water contact angle test demonstrated hydrophilicity of nanofibers with 47.35°. Although EO and AMX had little effect on reducing hydrophilicity but nanofibers with contact angle between 51.4° until 65.4° are still hydrophilic. Multilayer nanofibers loaded by EO and AMX killed 99.99 % of both gram-negative and gram-positive bacteria in comparison with control and PVA/gelatin nanofiber. Also, in addition to confirming the non-toxicity of nanofibers, MTT results also showed the acceleration of cell proliferation. In vivo wound evaluation in mouse models showed that designed nanofibrous scaffolds could be an appropriate option for wound treatment due to their positive effect on angiogenesis, collagen deposition, granulation tissue formation, epithelialization, and wound closure.

Perspectives on antimicrobial properties of Paulownia tomentosa Steud. fruit products in the control of Staphylococcus aureus infections

ETHNOPHARMACOLOGICAL RELEVANCE

Paulownia tomentosa Steud. (P. tomentosa) is a medium-sized tree traditionally used in Chinese folk medicine for the treatment of infectious diseases. It is a rich source of prenylated phenolic compounds that have been extensively studied for their promising biological activities.

AIM OF THE STUDY

Due to the increasing development of antibiotic resistance, our study investigated plant-derived natural products from the fruits of P. tomentosa that could control Staphylococcus aureus infections with novel targets/modes of action and reduce antimicrobial resistance.

MATERIALS AND METHODS

The ethanolic extract was fractionated and detected by liquid chromatography. The antistaphylococcal effects of the plant formulations were studied in detail in vitro by various biological methods, including microdilution methods for minimum inhibitory concentration (MIC), the checkerboard titration technique for synergy assay, fluorescence measurements for membrane disruption experiments, autoinducer-2-mediated bioassay for quorum sensing inhibition, and counting of colony-forming units for relative adhesion. Morphology was examined by transmission electron microscopy.

RESULTS

Total ethanolic extract and chloroform fraction showed MICs of 128 and 32 μg/mL, respectively. Diplacol, diplacone, and 3'-O-methyl-5'-hydroxydiplacone inhibited S. aureus growth in the range of 8-16 μg/mL. Synergistic potential was shown in combination with mupirocin and fusidic acid. The ethanolic extract and the chloroform fraction destroyed the cell membranes by 91.61% and 79.46%, respectively, while the pure compounds were less active. The ethanolic extract and the pure compounds reduced the number of adhered cells to 47.33-10.26% compared to the untreated control. All tested plant formulations, except diplacone, inhibited quorum sensing of S. aureus. Transmission electron microscopy showed deformation of S. aureus cells.

CONCLUSIONS

The products from the fruit of P. tomentosa showed antimicrobial properties against S. aureus alone and in combination with antibiotics. By affecting intracellular targets, geranylated flavonoids proposed novel approaches in the control of staphylococcal infections.

Clinical effectiveness of orange peel polymethoxy-flavonoids rich fraction as a palatal dressing material compared to Alveogyl: randomized clinical trial

This study assessed the clinical effectiveness of orange peel polymethoxy-flavonoids rich fraction (OPMF) solid dispersion as a palatal dressing material, compared with Alveogyl, in a randomized clinical trial. After harvesting free gingival grafts for 18 patients in three groups, the donor site in group I received OPMF; group II received Alveogyl; and group III received placebo dough material. The visual analog scale (VAS) pain score in group I showed the lowest value in week one without a significant difference. In week 2, there was a substantial decrease in pain in group I compared to group III. Week 4 showed reduced pain scores in all groups without significant differences. The results of the number of analgesic pills revealed, after 1 week, the lowest number of pills consumed in group I, with a considerable difference compared to group III. Healing process results showed that group I had the highest healing values in each interval, with a significant difference between group I and group III at 1 and 2 weeks. Color matching parameter showed slight differences between the groups' readings in favor of group I in all intervals without a statistically significant difference. The results suggest OPMF as a palatal dressing material that facilitates hemostasis, pain relief, and palatal wound healing.

Multifunctional lipid-based nanoparticles for wound healing and antibacterial applications: A review

Wound healing primarily involves preventing severe infections, accelerating healing, and reducing pain and scarring. Therefore, the multifunctional application of lipid-based nanoparticles (LBNs) has received considerable attention in drug discovery due to their solid or liquid lipid core, which increases their ability to provide prolonged drug release, reduce treatment costs, and improve patient compliance. LBNs have also been used in medical and cosmetic practices and formulated for various products based on skin type, disease conditions, administration product costs, efficiency, stability, and toxicity; therefore, understanding their interaction with biological systems is very important. Therefore, it is necessary to perform an in-depth analysis of the results from a comprehensive characterization process to produce lipid-based drug delivery systems with desired properties. This review will provide detailed information on the different types of LBNs, their formulation methods, characterisation, antimicrobial activity, and application in various wound models (both in vitro and in vivo studies). Also, the clinical and commercial applications of LBNs are summarized.

Oligochitosan and oxidized nucleoside-based bioderived hydrogels for wound healing

Herein, we report biocompatible hydrogel for wound healing that was prepared using nature-sourced building blocks. For the first time, OCS was employed as a building macromolecule to form bulk hydrogels along with the nature-sourced nucleoside derivative (inosine dialdehyde, IdA) as the cross-linker. A strong correlation was obtained between the mechanical properties and stability of the prepared hydrogels with a cross-linker concentration. The Cryo-SEM images of IdA/OCS hydrogels showed an interconnected spongy-like porous structure. Alexa 555 labeled bovine serum albumin was incorporated into the hydrogels matrix. The release kinetics studies under physiological conditions indicated that cross-linker concentration could also control the release rate. The potential of hydrogels in wound healing applications was tested in vitro and ex vivo on human skin. Topical application of the hydrogel was excellently tolerated by the skin with no impairment of epidermal viability or irritation, determined by MTT and IL-1α assays, respectively. The hydrogels were used to load and deliver epidermal growth factor (EGF), showing an increase in its ameliorating action, effectively enhancing wound closure inflicted by punch biopsy. Furthermore, BrdU incorporation assay performed in both fibroblast and keratinocyte cells revealed an increased proliferation in hydrogel-treated cells and an enhancement of EGF impact in keratinocytes.

Investigation of the phytochemical composition, antioxidant, antibacterial, anti-osteoarthritis, and wound healing activities of selected vegetable waste

Agri-food wastes, produced following industrial food processing, are mostly discarded, leading to environmental hazards and losing the nutritional and medicinal values associated with their bioactive constituents. In this study, we performed a comprehensive analytical and biological evaluation of selected vegetable by-products (potato, onion, and garlic peels). The phytochemical analysis included UHPLC-ESI-qTOF-MS/MS in combination with molecular networking and determination of the total flavonoid and phenolic contents. Further, the antimicrobial, anti-osteoarthritis and wound healing potentials were also evaluated. In total, 47 compounds were identified, belonging to phenolic acids, flavonoids, saponins, and alkaloids as representative chemical classes. Onion peel extract (OPE) showed the higher polyphenolic contents, the promising antioxidant activity, the potential anti-osteoarthritis activity, and promising antimicrobial activity, especially against methicillin-resistant Staphylococcus aureus (MRSA). Furthermore, OPE revealed to have promising in vivo wound healing activity, restoring tissue physiology and integrity, mainly through the activation of AP-1 signaling pathway. Lastly, when OPE was loaded with nanocapsule based hydrogel, the nano-formulation revealed enhanced cellular viability. The affinities of the OPE major metabolites were evaluated against both p65 and ATF-2 targets using two different molecular docking processes revealing quercetin-3,4'-O-diglucoside, alliospiroside C, and alliospiroside D as the most promising entities with superior binding scores. These results demonstrate that vegetable by-products, particularly, those derived from onion peels can be incorporated as natural by-product for future evaluation against wounds and osteoarthritis.

Wound healing effects of Asparagus lucidus Lindl extract through the phosphorylation of ERK1/2

BACKGROUND

Skin is the outermost part of the human body and is essential in maintaining body homeostasis. In the event of skin injury, rapid wound repair is crucial to protect the body. In this study, we investigated the wound-healing properties of Asparagus lucidus Lindl extract by promoting keratinocyte proliferation.

METHODS

To evaluate the effect of Asparagus lucidus Lindl extract on skin regeneration, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to measure keratinocyte proliferation, while an in vitro wound-healing assay was performed to evaluate wound closure through keratinocyte re-epithelialization. The intracellular mechanisms of the extract were studied using Western blot analysis to measure the phosphorylated forms of mitogen-activated protein kinases and protein kinase B. The mRNA expression of cell cycle-related genes was analyzed using quantitative real time-PCR analysis. A murine in vivo wound-healing assay was also conducted to observe the effect of the extract on wound closure.

RESULTS

Asparagus lucidus Lindl extract induced 131.15% keratinocyte proliferation compared to the control in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The in vitro wound-healing assay showed that the extract improved wound closure by 216.94% through keratinocyte re-epithelialization. Western blot analysis revealed that the phosphorylated form of extracellular signal-regulated kinase 1/2 was increased by extract treatment. Quantitative real time-PCR analysis showed a dose-dependent increase in the mRNA expression of c-fos, c-jun, and VEGF. The in vivo wound-healing assay showed a significant increase (22.13%) of wound closure compared to the control on day 5.

CONCLUSION

Asparagus lucidus Lindl extract promotes keratinocyte proliferation by activating the extracellular signal-regulated kinase 1/2 pathway and up-regulating the mRNA expression of c-fos, c-jun, and vascular endothelial growth factor.

Combining Polymer and Cyclodextrin Strategy for Drug Release of Sulfadiazine from Electrospun Fibers

This study reports the fabrication of polymeric matrices through electrospinning using polymethyl methacrylate (PMMA) and poly(lactic-co-glycolic acid) (PLGA), biocompatible polymers commonly used in medical systems. These polymers were combined with an antibacterial drug, sulfadiazine sodium salt (SDS) or its supramolecular system formed with hydroxypropyl-β-cyclodextrin (HPβ/CD) at 1:1 molar ratio, aiming to assemble a transdermal drug delivery system. The formation of fibers was confirmed by scanning electron microscopy (SEM), and the fibers' surface properties were analyzed using contact angle and water vapor permeability techniques. Drug release tests and cell viability assays were performed to evaluate the potential toxicity of the material. SEM images demonstrated that the obtained fibers had nanoscale- and micrometer-scale diameters in PLGA and PMMA systems, respectively. The contact angle analyses indicated that, even in the presence of hydrophilic molecules (SDS and HPβCD), PMMA fibers exhibited hydrophobic characteristics, while PLGA fibers exhibited hydrophilic surface properties. These data were also confirmed by water vapor permeability analysis. The drug release profiles demonstrated a greater release of SDS in the PLGA system. Moreover, the presence of HPβCD improved the drug release in both polymeric systems and the cell viability in the PMMA SDS/HPβCD system. In terms of antibacterial activity, all membranes yielded positive outcomes; nevertheless, the PLGA SDS/HPβCD membrane exhibited the most remarkable results, with the lowest microbial load values. Additionally, the pseudo wound healing analysis demonstrated that the PLGA SDS/HPβCD fiber exhibited results similar to the control group. Consequently, these findings exemplify the substantial potential of the obtained materials for use in wound healing applications.

Antimicrobial activity and wound healing effect of a novel natural ointment: an in vitro and in vivo study

Infection and pathological disorders, such as cellular disorders, ischaemia, neuropathy and angiogenesis, are considered the most critical factors which cause a delay in the wound healing process in patients with diabetes. This study aimed to investigate the effect of an ointment based on ostrich oil containing honey, beeswax, and ethanolic extracts of Nigella sativa, propolis and Cassia angustifolia on the wound healing process of diabetic rats. Gas chromatography/mass spectrometry analysis showed caffeic acid and pinostrobin chalcone molecules present in propolis, giving antibacterial and antifungal properties to the compound. The antibacterial assessment showed the ointment had remarkable antibacterial activity against Staphylococcus aureus (8.6±0.28mm), Escherichia coli (9.4±0.31mm), Acinetobacter baumannii (7.2±0.23mm) and Pseudomonas aeruginosa (13.9±0.42mm). In vivo results showed the ointment significantly accelerated wound healing and increased collagen deposition compared with the control (p<0.05). Histopathology evaluation also showed hair follicles, sebaceous glands and vessels in the group that used the ointment. These results proved successful and diabetic wound healing was rapid. Therefore, it could be concluded that the fabricated ointment could be a suitable candidate for wound healing.

Phytochemistry and pharmacology of natural prenylated flavonoids

Prenylated flavonoids are a special kind of flavonoid derivative possessing one or more prenyl groups in the parent nucleus of the flavonoid. The presence of the prenyl side chain enriched the structural diversity of flavonoids and increased their bioactivity and bioavailability. Prenylated flavonoids show a wide range of biological activities, such as anti-cancer, anti-inflammatory, neuroprotective, anti-diabetic, anti-obesity, cardioprotective effects, and anti-osteoclastogenic activities. In recent years, many compounds with significant activity have been discovered with the continuous excavation of the medicinal value of prenylated flavonoids, and have attracted the extensive attention of pharmacologists. This review summarizes recent progress on research into natural active prenylated flavonoids to promote new discoveries of their medicinal value.

Flavonoids as Potential Wound-Healing Molecules: Emphasis on Pathways Perspective

Wounds are considered to be a serious problem that affects the healthcare sector in many countries, primarily due to diabetes and obesity. Wounds become worse because of unhealthy lifestyles and habits. Wound healing is a complicated physiological process that is essential for restoring the epithelial barrier after an injury. Numerous studies have reported that flavonoids possess wound-healing properties due to their well-acclaimed anti-inflammatory, angiogenesis, re-epithelialization, and antioxidant effects. They have been shown to be able to act on the wound-healing process via expression of biomarkers respective to the pathways that mainly include Wnt/β-catenin, Hippo, Transforming Growth Factor-beta (TGF-β), Hedgehog, c-Jun N-Terminal Kinase (JNK), NF-E2-related factor 2/antioxidant responsive element (Nrf2/ARE), Nuclear Factor Kappa B (NF-κB), MAPK/ERK, Ras/Raf/MEK/ERK, phosphatidylinositol 3-kinase (PI3K)/Akt, Nitric oxide (NO) pathways, etc. Hence, we have compiled existing evidence on the manipulation of flavonoids towards achieving skin wound healing, together with current limitations and future perspectives in support of these polyphenolic compounds as safe wound-healing agents, in this review.

3D Printing as a Technological Strategy for the Personalized Treatment of Wound Healing

Wound healing is a dynamic process which involves stages of hemostasis, inflammation, proliferation and remodeling. Any error in this process results in abnormal wound healing, generating financial burdens for health systems and even affecting the physical and mental health of the patient. Traditional dressings do not meet the complexities of ideal treatment in all types of wounds. For this reason, in the last decades, different materials for drug delivery and for the treatment of wounds have been proposed reaching novel level of standards, such as 3D printing techniques. The use of natural or synthetic polymers, and the correct design of these printed products loaded with cells and/or combined with active compounds, can generate an effective system for the treatment of wounds, improving the healing process and generating customized dressings according to the patient needs. This manuscript provides a comprehensive review of different types of 3D printing techniques, as well as its use in wound healing and its different stages, including the advantages and limitations of additive manufacturing and future perspectives.

The Wound Healing Potential of Lignosus rhinocerus and Other Ethno-myco Wound Healing Agents

Wound care has become increasingly important over the years. Various synthetic products for wound care treatment have been reported to cause toxic side effects and therefore natural products are in significant demand as they have minimal side effects. The presence of bioactive compounds in medicinal mushrooms contributes to various biological activities which assist in the early inflammatory phase, keratinocyte proliferation, and its migration enhancement which are pertinent to wound rehabilitation. Lignosus rhinocerus (tiger milk mushroom) can reduce the inflammation phase in wound healing by fighting off bacterial infection and modulating pro-inflammatory cytokines expression in the early stage to avoid prolonged inflammation and tissue damage. The antibacterial, immunomodulating, and anti-inflammatory activities exhibited by most macrofungi play a key role in enhancing wound healing. Several antibacterial and antifungal compounds sourced from traditional botanicals/products may prevent further complications and reoccurrence of injury to a wounded site. Scientific studies are actively underway to ascertain the potential use of macrofungi as a wound healing agent.

Antioxidant, Anti-Inflammation and Antiaging Activities of Artocarpus altilis Methanolic Extract on Urban Particulate Matter-Induced HaCaT Keratinocytes Damage

Particulate matter (PM) is one of the reasons that exacerbate skin diseases. Impaired barrier function is a common symptom in skin diseases, including atopic dermatitis, eczema and psoriasis. Herbal extracts rich in antioxidants are thought to provide excellent pharmacological activities; however, the anti-pollution activity of Artocarpus altilis extract (AAM) has not been investigated yet. The present study demonstrated that 5 μg/mL of AAM was considered to be a safe dose for further experiments without cytotoxicity. Next, we evaluated the anti-pollution activity of AAM through the PM-induced keratinocytes damage cell model. The results showed that AAM could reduce PM-induced overproduction of intracellular ROS and the final product of lipid peroxidation, 4-hydroxynonenal (4HNE). In addition, AAM not only reduced the inflammatory protein expressions, including tumor necrosis factor α (TNFα), TNF receptor 1 (TNFR1) and cyclooxygenase-2 (COX-2), but also balanced the aging protein ratio of matrix metalloproteinase (MMPs) and tissue inhibitors of metalloproteases (TIMPs) through downregulating the phosphorylation of mitogen-activated protein kinase (MAPK) signaling. For skin barrier protection, AAM could repair PM-induced barrier function proteins damage, including filaggrin, loricrin and aquaporin 3 for providing anti-aging bioactivity. In conclusion, AAM has the potential to be developed as an anti-pollution active ingredient for topical skin products to prevent skin oxidation, inflammation and aging, and restore the skin barrier function.

A Comprehensive Review of Natural Compounds for Wound Healing: Targeting Bioactivity Perspective

Wound healing is a recovering process of damaged tissues by replacing dysfunctional injured cellular structures. Natural compounds for wound treatment have been widely used for centuries. Numerous published works provided reviews of natural compounds for wound healing applications, which separated the approaches based on different categories such as characteristics, bioactivities, and modes of action. However, current studies provide reviews of natural compounds that originated from only plants or animals. In this work, we provide a comprehensive review of natural compounds sourced from both plants and animals that target the different bioactivities of healing to promote wound resolution. The compounds were classified into four main groups (i.e., anti-inflammation, anti-oxidant, anti-bacterial, and collagen promotion), mostly studied in current literature from 1992 to 2022. Those compounds are listed in tables for readers to search for their origin, bioactivity, and targeting phases in wound healing. We also reviewed the trend in using natural compounds for wound healing.

Modified hyaluronic acid-collagen matrices trigger efficient gene transfer and prohealing behavior in fibroblasts for improved wound repair

Growth factor therapy has demonstrated great promise for chronic wound repair, but controlling growth factor activity and cell phenotype over desired time frames remains a critical challenge. In this study, we developed a gene-activated hyaluronic acid-collagen matrix (GAHCM) comprising DNA/polyethylenimine (PEI) polyplexes retained on hyaluronic acid (HA)-collagen hydrogels using collagen mimetic peptides (CMPs). We hypothesized that manipulating both the number of CMP-collagen tethers and the ECM composition would provide a powerful strategy to control growth factor gene transfer kinetics while regulating cell behavior, resulting in enhanced growth factor activity for wound repair. We observed that polyplexes with 50% CMP-modified PEI (50 CP) showed enhanced retention of polyplexes in HCM hydrogels by 2.7-fold as compared to non-CMP modified polyplexes. Moreover, the incorporation of HA in the hydrogel promoted a significant increase in gene transfection efficiency based upon analysis of Gaussia luciferase (GLuc) reporter gene expression, and gene expression could be attenuated by blocking HA-CD44 signaling. Furthermore, when fibroblasts were exposed to vascular endothelial growth factor-A (VEGF-A)-GAHCM, the 50 CP matrix facilitated sustained VEGF-A production for up to 7 days, with maximal expression at day 5. Application of these VEGF-A-50 CP samples stimulated prolonged pro-healing responses, including the TGF-β1-induced myofibroblast-like phenotypes and enhanced closure of murine splinted wounds. Overall, these findings demonstrate the use of ECM-based materials to stimulate efficient gene transfer and regulate cellular phenotype, resulting in improved control of growth factor activity for wound repair. GAHCM have significant potential to overcome key challenges in growth factor therapy for regenerative medicine. STATEMENT OF SIGNIFICANCE: Despite great promise for growth factor therapies in wound treatment, controlling growth factor activity and providing a microenvironment for cells that maximizes growth factor signaling have continued to limit the success of existing formulations. Our GAHCM strategy, combining CMP gene delivery and hyaluronic acid-collagen matrix, enabled enhanced wound healing efficacy via the combination of controlled and localized growth factor expression and matrix-mediated regulation of cell behavior. Incorporation of CMPs and HA in the same matrix synergistically enhanced VEGF activity as compared with simpler matrices. Accordingly, GAHCM will advance our ability to leverage growth factor signaling for wound healing, resulting in new long-term treatments for recalcitrant wounds.

Prenylated Flavonoids in Topical Infections and Wound Healing

The review presents prenylated flavonoids as potential therapeutic agents for the treatment of topical skin infections and wounds, as they can restore the balance in the wound microenvironment. A thorough two-stage search of scientific papers published between 2000 and 2022 was conducted, with independent assessment of results by two reviewers. The main criteria were an MIC (minimum inhibitory concentration) of up to 32 µg/mL, a microdilution/macrodilution broth method according to CLSI (Clinical and Laboratory Standards Institute) or EUCAST (European Committee on Antimicrobial Susceptibility Testing), pathogens responsible for skin infections, and additional antioxidant, anti-inflammatory, and low cytotoxic effects. A total of 127 structurally diverse flavonoids showed promising antimicrobial activity against pathogens affecting wound healing, predominantly Staphylococcus aureus strains, but only artocarpin, diplacone, isobavachalcone, licochalcone A, sophoraflavanone G, and xanthohumol showed multiple activity, including antimicrobial, antioxidant, and anti-inflammatory along with low cytotoxicity important for wound healing. Although prenylated flavonoids appear to be promising in wound therapy of humans, and also animals, their activity was measured only in vitro and in vivo. Future studies are, therefore, needed to establish rational dosing according to MIC and MBC (minimum bactericidal concentration) values, test potential toxicity to human cells, measure healing kinetics, and consider formulation in smart drug release systems and/or delivery technologies to increase their bioavailability.

4-Aminopyridine Induces Nerve Growth Factor to Improve Skin Wound Healing and Tissue Regeneration

The discovery of ways to enhance skin wound healing is of great importance due to the frequency of skin lesions. We discovered that 4-aminopyridine (4-AP), a potassium channel blocker approved by the FDA for improving walking ability in multiple sclerosis, greatly enhances skin wound healing. Benefits included faster wound closure, restoration of normal-appearing skin architecture, and reinnervation. Hair follicle neogenesis within the healed wounds was increased, both histologically and by analysis of K15 and K17 expression. 4-AP increased levels of vimentin (fibroblasts) and alpha-smooth muscle actin (α-SMA, collagen-producing myofibroblasts) in the healed dermis. 4-AP also increased neuronal regeneration with increased numbers of axons and S100⁺ Schwann cells (SCs), and increased expression of SRY-Box Transcription Factor 10 (SOX10). Treatment also increased levels of transforming growth factor-β (TGF-β), substance P, and nerve growth factor (NGF), important promoters of wound healing. In vitro studies demonstrated that 4-AP induced nerve growth factor and enhanced proliferation and migration of human keratinocytes. Thus, 4-AP enhanced many of the key attributes of successful wound healing and offers a promising new approach to enhance skin wound healing and tissue regeneration.

Cutaneous Regeneration Mechanism of β-Sheet Silk Fibroin in a Rat Burn Wound Healing Model

Therapeutic dressings to enhance burn wound repair and regeneration are required. Silk fibroin (SF), a natural protein, induces cell migration and serves as a biomaterial in various dressings. SF dressings usually contain α-helices and β-sheets. The former has been confirmed to improve cell proliferation and migration, but the wound healing effect and related mechanisms of β-sheet SF remain unclear. We investigated the effects of β-sheet SF in vivo and in vitro. Alcohol-treated α-helix SF transformed into the β-sheet form, which promoted granulation formation and re-epithelialization when applied as lyophilized SF dressing (LSFD) in a rat burn model. Our in vitro results showed that β-sheet SF increased human dermal fibroblast (HDF) migration and promoted the expression of extracellular matrix (ECM) proteins (fibronectin and type III collagen), matrix metalloproteinase-12, and the cell adhesion molecule, integrin β1, in rat granulation tissue and HDFs. This confirms the role of crosstalk between integrin β1 and ECM proteins in cell migration. In summary, we demonstrated that β-sheet SF facilitates tissue regeneration by modulating cell adhesion molecules in dermal fibroblasts. LSFD could find clinical application for burn wound regeneration. Moreover, β-sheet SF could be combined with anti-inflammatory materials, growth factors, or antibiotics to develop novel dressings.

The Antimicrobial Peptide Human β-Defensin-3 Accelerates Wound Healing by Promoting Angiogenesis, Cell Migration, and Proliferation Through the FGFR/JAK2/STAT3 Signaling Pathway

In addition to its antimicrobial activity, the skin-derived antimicrobial peptide human β-defensin-3 (hBD-3) promotes keratinocyte proliferation and migration to initiate the wound healing process; however, its effects on fibroblasts, which are the major cell type responsible for wound healing, remain unclear. We investigated the role of hBD-3 in cell migration, proliferation and production of angiogenic growth factors in human fibroblasts and evaluated the in vivo effect of hBD-3 on promoting wound healing and angiogenesis. Following hBD-3 treatment, the mouse wounds healed faster and showed accumulation of neutrophils and macrophages in the early phase of wound healing and reduction of these phagocytes 4 days later. hBD-3-treated wounds also displayed an increased number of fibroblasts and newly formed vessels compared to those of the control mice. Furthermore, the expression of various angiogenic growth factors was increased in the hBD-3-treated wounds. Additionally, in vitro studies demonstrated that hBD-3 enhanced the secretion of angiogenic growth factors such as fibroblast growth factor, platelet-derived growth factor and vascular endothelial growth factor and induced the migration and proliferation of human fibroblasts. The hBD-3-mediated activation of fibroblasts involves the fibroblast growth factor receptor 1 (FGFR1)/Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathways, as evidenced by the inhibitory effects of pathway-specific inhibitors. We indeed confirmed that hBD-3 enhanced the phosphorylation of FGFR1, JAK2 and STAT3. Collectively, the current study provides novel evidence that hBD-3 might be a potential candidate for the treatment of wounds through its ability to promote wound healing, angiogenesis and fibroblast activation.

Topical Artocarpus communis Nanoparticles Improved the Water Solubility and Skin Permeation of Raw A. communis Extract, Improving Its Photoprotective Effect

Antioxidants from plant extracts are often used as additives in skincare products to prevent skin problems induced by environmental pollutants. Artocarpus communis methanol extract (ACM) has many biological effects, such as antioxidant, anti-inflammatory, wound healing, and photoprotective effects; however, the poor water solubility of raw ACM has limited its applications in medicine and cosmetics. Topical antioxidant nanoparticles are one of the drug-delivery systems for overcoming the poor water solubility of antioxidants for increasing their skin penetration. The present study demonstrated that ACM-loaded hydroxypropyl-β-cyclodextrin and polyvinylpyrrolidone K30 nanoparticles (AHP) were successfully prepared and could effectively increase the skin penetration of ACM through changing the physicochemical characteristics of raw ACM, including reducing the particle size, increasing the surface area, and inducing amorphous transformation. Our results also revealed that AHP had significantly better antioxidant activity than raw ACM for preventing photocytotoxicity because the AHP formulation increased the cellular uptake of the ACM in UVB-irradiated HaCaT keratinocytes. In conclusion, our results suggest that AHP may be used as a good topical antioxidant nanoparticle for delivering ACM into deep layers of the skin for preventing UVB-induced skin problems.

Dracorhodin perchlorate enhances wound healing via β-catenin, ERK/p38, and AKT signaling in human HaCaT keratinocytes

Dracorhodin can be isolated from the exudates of the fruit of Daemonorops draco. Previous studies suggested that dracorhodin perchlorate can promote fibroblast proliferation and enhance angiogenesis during wound healing. In the present study, the potential bioactivity of dracorhodin perchlorate in human HaCaT keratinocytes, were investigated in vitro, with specific focus on HaCaT wound healing. The results of in vitro scratch assay demonstrated the progressive closure of the wound after treatment with dracorhodin perchlorate in a time-dependent manner. An MTT assay and propidium iodide exclusion detected using flow cytometry were used to detect cell viability of HaCaT cells. Potential signaling pathways underlying the effects mediated by dracorhodin perchlorate in HaCaT cells were clarified by western blot analysis and kinase activity assays. Dracorhodin perchlorate significantly increased the protein expression levels of β-catenin and activation of AKT, ERK and p38 in HaCaT cells. In addition, dracorhodin perchlorate did not induce HaCaT cell proliferation but promoted cell migration. Other mechanisms may yet be involved in the dracorhodin perchlorate-induced wound healing process of human keratinocytes. In summary, dracorhodin perchlorate may serve to be a potential molecularly-targeted phytochemical that can improve skin wound healing.

Artocarpin Targets Focal Adhesion Kinase-Dependent Epithelial to Mesenchymal Transition and Suppresses Migratory-Associated Integrins in Lung Cancer Cells

Focal adhesion kinase (FAK) controls several cancer aggressive potentials of cell movement and dissemination. As epithelial–mesenchymal transition (EMT) and the migratory-associated integrins, known influencers of metastasis, have been found to be linked with FAK activity, this study unraveled the potential pharmacological effect of artocarpin in targeting FAK resulting in the suppression of EMT and migratory behaviors of lung cancer cells. Treatment with artocarpin was applied at concentrations of 0–10 μM, and the results showed non-cytotoxicity in lung cancer cell lines (A549 and H460), normal lung (BEAS-2B) cells and primary metastatic lung cancer cells (ELC12, ELC16, and ELC20). We also found that artocarpin (0–10 µM) had no effect on cell viability, proliferation, and migration in BEAS-2B cells. For metastasis-related approaches, artocarpin significantly inhibited cell migration, invasion, and filopodia formation. Artocarpin also dramatically suppressed anchorage-independent growth, cancer stem cell (CSC) spheroid formation, and viability of CSC-rich spheroids. For molecular targets of artocarpin action, computational molecular docking revealed that artocarpin had the best binding affinity of −8.0 kcal/mol with FAK protein. Consistently, FAK-downstream proteins, namely active Akt (phosphorylated Akt), active mTOR (phosphorylated mTOR), and Cdc42, and EMT marker and transcription factor (N-cadherin, Vimentin, and Slug), were found to be significantly depleted in response to artocarpin treatment. Furthermore, we found the decrease of Caveolin-1 (Cav-1) accompanied by the reduction of integrin-αν and integrin-β3. Taken together, these findings support the anti-metastasis potentials of the compound to be further developed for cancer therapy.

Potential chemopreventive, anticancer and anti-inflammatory properties of a refined artocarpin-rich wood extract of Artocarpus heterophyllus Lam

Colorectal cancer (CRC) represents the third leading cause of death among cancer patients below the age of 50, necessitating improved treatment and prevention initiatives. A crude methanol extract from the wood pulp of Artocarpus heterophyllus was found to be the most bioactive among multiple others, and an enriched extract containing 84% (w/v) artocarpin (determined by HPLC–MS–DAD) was prepared. The enriched extract irreversibly inhibited the activity of human cytochrome P450 CYP2C9, an enzyme previously shown to be overexpressed in CRC models. In vitro evaluations on heterologously expressed microsomes, revealed irreversible inhibitory kinetics with an IC₅₀ value of 0.46 µg/mL. Time- and concentration-dependent cytotoxicity was observed on human cancerous HCT116 cells with an IC₅₀ value of 4.23 mg/L in 72 h. We then employed the azoxymethane (AOM)/dextran sodium sulfate (DSS) colitis-induced model in C57BL/6 mice, which revealed that the enriched extract suppressed tumor multiplicity, reduced the protein expression of proliferating cell nuclear antigen, and attenuated the gene expression of proinflammatory cytokines (Il-6 and Ifn-γ) and protumorigenic markers (Pcna, Axin2, Vegf, and Myc). The extract significantly (p = 0.03) attenuated (threefold) the gene expression of murine Cyp2c37, an enzyme homologous to the human CYP2C9 enzyme. These promising chemopreventive, cytotoxic, anticancer and anti-inflammatory responses, combined with an absence of toxicity, validate further evaluation of A. heterophyllus extract as a therapeutic agent.

Adenosine Diphosphate Improves Wound Healing in Diabetic Mice Through P2Y12 Receptor Activation

Chronic wounds are a public health problem worldwide, especially those related to diabetes. Besides being an enormous burden to patients, it challenges wound care professionals and causes a great financial cost to health system. Considering the absence of effective treatments for chronic wounds, our aim was to better understand the pathophysiology of tissue repair in diabetes in order to find alternative strategies to accelerate wound healing. Nucleotides have been described as extracellular signaling molecules in different inflammatory processes, including tissue repair. Adenosine-5'-diphosphate (ADP) plays important roles in vascular and cellular response and is immediately released after tissue injury, mainly from platelets. However, despite the well described effect on platelet aggregation during inflammation and injury, little is known about the role of ADP on the multiple steps of tissue repair, particularly in skin wounds. Therefore, we used the full-thickness excisional wound model to evaluate the effect of local ADP application in wounds of diabetic mice. ADP accelerated cutaneous wound healing, improved new tissue formation, and increased both collagen deposition and transforming growth factor-β (TGF-β) production in the wound. These effects were mediated by P2Y12 receptor activation since they were inhibited by Clopidogrel (Clop) treatment, a P2Y12 receptor antagonist. Furthermore, P2Y1 receptor antagonist also blocked ADP-induced wound closure until day 7, suggesting its involvement early in repair process. Interestingly, ADP treatment increased the expression of P2Y12 and P2Y1 receptors in the wound. In parallel, ADP reduced reactive oxygen species (ROS) formation and tumor necrosis factor-α (TNF-α) levels, while increased IL-13 levels in the skin. Also, ADP increased the counts of neutrophils, eosinophils, mast cells, and gamma delta (γδ) T cells (Vγ4+ and Vγ5+ cells subtypes of γδ+ T cells), although reduced regulatory T (Tregs) cells in the lesion. In accordance, ADP increased fibroblast proliferation and migration, myofibroblast differentiation, and keratinocyte proliferation. In conclusion, we provide strong evidence that ADP acts as a pro-resolution mediator in diabetes-associated skin wounds and is a promising intervention target for this worldwide problem.

Amnion and collagen-based blended hydrogel improves burn healing efficacy on a rat skin wound model in the presence of wound dressing biomembrane

BACKGROUND

A burn wound is one of the most frequent and devastating injuries for patients which requires extensive care. Early treatment of burn wounds improves healing significantly.

OBJECTIVE

This study was designed to investigate the efficacy of amnion and collagen-based hydrogels on cutaneous burn wound healing in rats with covering membrane.

METHODS

We prepared a novel cell free hydrogel comprising human amnion, rabbit collagen, carboxymethyl cellulose sodium salt, citric acid, methyl paraben, propyl paraben, glycerin and triethanol amine. The wound covering membrane was developed from rabbit collagen and prawn shell chitosan. Beside swelling ratio, water absorption, equilibrium water content, gel fraction and spreadability analysis, in vitro cytotoxicity and biocompatibility tests were performed for the formulated hydrogels. Following the skin irritation study, second-degree burns were created on the dorsal region of the rats and the gels were applied with/without covering membrane to study the wound contraction and re-epithelialization period.

RESULTS

The formulated hydrogels were observed non-cytotoxic and compatible with human blood cells. No erythema and edema were found in skin irritation assay confirming the safety and applicability. Hydrogel consisting in a combination of amnion and collagen demonstrated significantly rapid wound healing, driven by complete re-epithelialization (16.75 ± 0.96 days) and closure by wound contraction (72 ± 3.27%, P < 0.0000009) when wound dressing membrane was used, whereas this gel alone healed about 62.5 ± 4.43% (P < 0.00001) and required 18.75 ± 0.50 days to complete re-epithelialization. Additionally, the gel with covering membrane treated group had maximum average body weight, food and water intake.

CONCLUSION

The amnion and collagen-based blended gel offers alternative possibilities to treat skin wounds when covered with film, which could overcome the limitations associated with modern therapeutic products such as high costs, long manufacturing times, complexities, storing, and presence of living biomaterials.

Mealworm Oil (MWO) Enhances Wound Healing Potential through the Activation of Fibroblast and Endothelial Cells

Mealworm and mealworm oil (MWO) have been reported to affect antioxidant, anti-coagulation, anti-adipogenic and anti-inflammatory activities. However, the function of MWO in wound healing is still unclear. In this study, we found that MWO induced the migration of fibroblast cells and mRNA expressions of wound healing factors such as alpha-smooth muscle actin (α-SMA), collagen-1 (COL-1) and vascular endothelial growth factor (VEGF) in fibroblast cells. The tube formation and migration of endothelial cells were promoted through the activation of VEGF/VEGF receptor-2 (VEGFR-2)-mediated downstream signals including AKT, extracellular signal-regulated kinase (ERK) and p38 by MWO-stimulated fibroblasts for angiogenesis. Moreover, we confirmed that MWO promoted skin wound repair by collagen synthesis, re-epithelialization and angiogenesis in an in vivo excisional wound model. These results demonstrate that MWO might have potential as a therapeutic agent for the treatment of skin wounds.

Lactobacillus rhamnosus CGMCC 1.3724 (LPR) Improves Skin Wound Healing and Reduces Scar Formation in Mice

Skin wounds are an important clinical problem which affects millions of people worldwide. The search for new therapeutic approaches to improve wound healing is needed. The present study aimed to evaluate the effects of the oral treatment with the skin-related probiotics Lactobacillus johnsonii LA1 (LJ), L. paracasei ST11 (LP), and L. rhamnosus LPR (LR) in a model of excisional skin wounds in Swiss mice. The animals received daily oral gavage of PBS or 1 × 10⁷ colony-forming units of LJ, LP, or LR, singly, beginning just after the creation of wounds until euthanasia. Blood flow was evaluated by laser Doppler perfusion imaging. Myeloperoxidase and N-acetyl-β-D-glucosaminidase activities were used to assess the accumulation of neutrophils and macrophages, respectively. The wound tissue was also collected for histological analyses (H&E, Toluidine blue, and Picrosirius red staining). The macroscopic wound closure rate was faster only in mice treated with LR, but not with LJ and LP, when compared to mice treated with PBS. Histological evaluations showed that treatment with LR stimulated wound epithelization when compared to PBS. Further analyses showed that wounds from LR-treated mice presented a significant decrease in macrophage (p < 0.001) and mast cell (p < 0.001) infiltration, along with improved angiogenesis (p < 0.001) and blood flow (p < 0.01). Of note, collagen deposition and scarring were reduced in LR-treated mice when compared to PBS-treated mice. In conclusion, our results show that the oral treatment with Lactobacillus rhamnosus accelerates skin wound closure and reduces scar, besides to reducing inflammation and fibrogenesis and improving angiogenesis in the wounded skin.

Wound Healing Activity of a Novel Formulation SKRIN via Induction of Cell Cycle Progression and Inhibition of PCNA-p21 Complex Interaction Leading to Cell Survival and Proliferation

The process of wound healing is a dynamic event that starts with inflammation, proliferation, and cell migration of various types of fibroblast cells. Therefore, identification of potential molecules which may increase the wound healing capacity of fibroblast cells is crucial. A novel hydroalcoholic formulation of belladonna (SKRIN), was developed and characterized by GC-MS/MS, DLS, TEM, and AFM and was found to contain atropine and scopolamine exhibit in aggregated nanosized particles. SKRIN-mediated fibroblast cell survival was elucidated in the presence of H₂O₂ by MTT and flow cytometry based assays. With an EC₅₀ of 4.41 μg/mL, SKRIN treatment showed significant increase in cell survival that was evident from a 1.11-fold increase (p < 0.0122) in the live cell population and 4.21-fold (p < 0.0001) and 2.59-fold (p < 0.0001) reductions in the early and late apoptotic cell populations, respectively. SKRIN-mediated wound healing was measured by cell scratch assay and cell cycle analysis. During the wound closure phenomenon, SKRIN increases repairing fibroblast cell proliferation by 1.24-fold (p = 0.0481) and increases the count of G2/M phase cells by 1.76-fold (p = 0.0002) which was confirmed by increased PCNA and reduced p21 protein expressions probably mediated by molecular interactions of PCNA-p21 complex with alkaloids present in SKRIN. Relative gene expression analysis further showed that SKRIN increases the PI3K, Akt, and NF-κB expression. Our data suggests that SKRIN exhibits wound healing property by increasing cell survival and repairing fibroblast proliferation via activation of the PI3K-Akt-NF-κB pathway probably mediated by inhibition of PCNA-p21 complex interaction.

Antioxidant and antibacterial polyelectrolyte wound dressing based on chitosan/hyaluronan/phosphatidylcholine dihydroquercetin

Antioxidant and antimicrobial wound dressings are the most favorable for acute and chronic wounds treatment. Herein, we formulated a multifunctional polyelectrolyte wound dressing membrane on the basis of chitosan (Ch) and hyaluronan (HA) enhanced by phosphatidylcholine dihydroquercetin (PCDQ). Physicochemical properties and microstructures of fabricated films were investigated adopting Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscope (SEM). Furthermore, water uptakes, wettability profiles, surface roughness, and mechanical characteristics of the developed membranes were studied. The developed wound dressing revealed free radical scavenging potency, hemocompatibility with a tendency to enhance blood clotting. Furthermore, incorporation of PCDQ significantly promoted the antibacterial and anti-inflammatory activities of Ch/HA/PCDQ. Moreover, Ch/HA/PCDQ films exhibited cellular compatibility towards mouse fibroblast cells. The capability of Ch/HA/PCDQ to promote wound healing was evaluated using adult Wistar albino female rats. The in vivo findings demonstrated that Ch/HA/PCDQ films significantly ameliorated mouse full-thickness wounds as evidenced by a reduction in the wound area. Moreover, histological examinations of wounds dressed with Ch/HA/PCDQ illustrated a prominent re-epithelialization compared with wounds handled with the cotton gauze and Ch/HA dressings, exposing the efficiency of PCDQ. These findings emphasized that a Ch/HA/PCDQ membrane has outstanding potential for wound healing and skin regeneration.

Crocodylus porosus: a potential source of anticancer molecules

Background

Cancer remains a global threat resulting in significant morbidity and mortality despite advances in therapeutic interventions, suggesting urgency for identification of anticancer agents. Crocodiles thrive in polluted habitat, feed on germ-infested meat, are exposed to carcinogenic heavy metals, are the very few species to survive the catastrophic Cretaceous–Paleogene extinction event, yet have a prolonged lifespan and rarely been reported to develop cancer. Therefore, we hypothesised that animals living in polluted environments such as crocodiles possess anticancer molecules/mechanisms.

Methods

Crocodylus porosus was procured, blood collected, dissected and lysates prepared from internal organs. Organ lysates and sera were tested for growth inhibition, cytotoxic effects and cell survival against HeLa, PC3 and MCF7 cells and subjected to liquid chromatography mass spectrometry. RNA transcriptome analysis and differential gene analysis were performed using Galaxy Bioinformatics.

Results

Sera exhibited potent growth inhibition and cytotoxic effects against cancer cells. 80 molecules were detected from C. porosus and 19 molecules were putatively identified. Additionally, more than 100 potential anticancer peptides were identified from sera using bioinformatics based on peptide amino acid composition, binary profile, dipeptide composition and pseudo-amino acid composition. Following transcriptome analysis, 14 genes in treated HeLa cells, 51 genes in treated MCF7 cells and 2 genes in treated PC3 cells, were found to be expressed, compared with untreated controls.

Conclusion

Animals residing in polluted milieus are an unexploited source for prospective pharmaceutical drugs, and could lead to identification of novel antitumour compound(s) and/or further understanding of the mechanisms of cancer resistance.

Drupin, a cysteine protease from Ficus drupacea latex accelerates excision wound healing in mice

Wound healing is a tightly regulated physiological process that restores tissue integrity after injury. Plant latex proteases (PLPs) are considered an integral part in herbal wound care as it interferes at different phases of the wound healing process. Although many studies have reported the involvement of PLPs in healing process, an in-depth investigation is required to understand the molecular mechanism. Hence, the effect of PLPs with fibrinolytic activity on wound healing was investigated systematically using mouse excision wound model. Among 29 latices from Ficus genus tested, Ficus drupacea exhibited potent fibrinolytic activity. Cysteine protease responsible for fibrinolysis was purified from the F. drupacea latex named it as drupin, tested for its wound healing efficacy. The accelerated wound healing was mediated by downregulation of matrix metalloprotease (MMP)-9 without altering MMP-8 expression. Besides, drupin enhanced the rate of collagen synthesis at the wound site by increasing arginase 1 activity. And also, drupin increased the expression of arginase 1 in macrophages and involved in cell proliferation, and migration via MAP kinase and PI3K/Akt pathways. Overall, the present study highlights the interference of drupin in wound healing by increased arginase 1 activity and collagen synthesis, and cell proliferation and migration.

A Review of the Contribution of Mast Cells in Wound Healing: Involved Molecular and Cellular Mechanisms

Mast cells (MCs), apart from their classic role in allergy, contribute to a number of biologic processes including wound healing. In particular, two aspects of their histologic distribution within the skin have attracted the attention of researchers to study their wound healing role; they represent up to 8% of the total number of cells within the dermis and their cutaneous versions are localized adjacent to the epidermis and the subdermal vasculature and nerves. At the onset of a cutaneous injury, the accumulation of MCs and release of proinflammatory and immunomodulatory mediators have been well documented. The role of MC-derived mediators has been investigated through the stages of wound healing including inflammation, proliferation, and remodeling. They contribute to hemostasis and clot formation by enhancing the expression of factor XIIIa in dermal dendrocytes through release of TNF-α, and contribute to clot stabilization. Keratinocytes, by secreting stem cell factor (SCF), recruit MCs to the site. MCs in return release inflammatory mediators, including predominantly histamine, VEGF, interleukin (IL)-6, and IL-8, that contribute to increase of endothelial permeability and vasodilation, and facilitate migration of inflammatory cells, mainly monocytes and neutrophils to the site of injury. MCs are capable of activating the fibroblasts and keratinocytes, the predominant cells involved in wound healing. MCs stimulate fibroblast proliferation during the proliferative phase via IL-4, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) to produce a new extracellular matrix (ECM). MC-derived mediators including fibroblast growth factor-2, VEGF, platelet-derived growth factor (PDGF), TGF-β, nerve growth factor (NGF), IL-4, and IL-8 contribute to neoangiogenesis, fibrinogenesis, or reepithelialization during the repair process. MC activation inhibition and targeting the MC-derived mediators are potential therapeutic strategies to improve wound healing through reduced inflammatory responses and scar formation.

Efficacy of application of Equisetum pyramidale Goldm. hydrogel for tissue restoration of induced skin lesions in Wistar rats

Medicinal plants, such as E. pyramidale, are alternatives against infections and assist in the healing process of wounds. We evaluated the effects of Hydrogel of E. pyramidale on the healing of cutaneous wounds in animal models by morphological, morphometric and histological analyses, and elucidated major components. The ethanolic extract of E. pyramidale shoots was submitted to phytochemical analysis. For cicatrizing activity assay, Wistar rats were used, and the groups evaluated were hydrogel containing ethanolic extract of E. pyramidale at 2% compared to control groups. The treatment periods were 3, 7 and 21 days, and macroscopic and microscopic analyses were performed. Data were submitted to Analysis of Variance (p <0.05). Phytochemistry and quantification evidenced that flavonoids are main constituents and that they were evidenced by thin layer chromatography (TLC), high efficiency (HPLC) and infrared (IR) methods. In TLC, using flavonoid patterns, we observed pinocembrin. The hydrogel containing ethanolic extract of E. pyramidale at 2% was effective in wound regression. E. pyramidale can be used for the treatment of second intention wounds, and the effective healing may be due to a high flavonoid content.

Macrophage mediation in normal and diabetic wound healing responses

PURPOSE

The failure in timely healing of wounds is a central feature in chronic wounds that leads to physiological, psychological and economic burdens. Macrophages have been demonstrated to have various functions in wounds including host defense, the promotion and resolution of inflammation, the removal of apoptotic cells and tissue restoration following injury. Accumulated evidence suggests that macrophage dysfunction is a component of the pathogenesis of non-healing wounds. While the overall signaling cascades have been well understood, their complex interplay and a detailed characterization of events that are disrupted in chronic wounds have still not emerged satisfactorily.

METHODS

The existing literature was reviewed to summarize the regulation of macrophage polarization in wound closure and dysregulation in non-healing wounds. Further, the review also underscored the role of Nrf2 in promoting macrophage-mediated regulation in wound responses and in particular, macrophage involvement in iron homeostasis that is impaired in chronic wounds such as in diabetes.

RESULTS

The mechanisms involved in the reprogramming of macrophage subtypes in chronic wounds are still emerging. Furthermore, treating non-healing wounds has increasingly been shifting focus from generic treatments to the development of targeted therapies. Increasing evidence suggests the need for modeling wound tissue in vitro which may very well serve a critical aspect to characterize the relevant factors that sustain chronic wounds in vivo such as the constant iron overload at the wound site from recurrent infection and bleeding.

CONCLUSION

The development of targeted therapies and also developing a reliable means to monitor assisted healing of chronic wounds are two major goals to be pursued. In addition, identifying molecular targets that can regulate macrophages to aid tissue restoration in chronic wounds would serve the crucial step in realizing both aforementioned goals.

In Vitro and in Vivo Studies of pH-Sensitive GHK-Cu-Incorporated Polyaspartic and Polyacrylic Acid Superabsorbent Polymer

The main aim of this study was to evaluate the in vitro and in vivo efficiency of the polyaspartic acid- and acrylic acid-based superabsorbent polymer. The synthesized polymer was first investigated to check the blood compatibility by protein adsorption and blood clotting tests. Further, the GHK-Cu peptide was incorporated within the polymer and release studies were performed to evaluate the drug-delivery efficiency of the superabsorbent polymer. The polymer with best peptide release results were further used for in vivo analysis for wound healing. The healing efficiency of polymer with and without peptide was analyzed using wound closure, biochemical assay, histopathological, and toxicity studies.

α-Bisabolol-Loaded Cross-Linked Zein Nanofibrous 3D-Scaffolds For Accelerating Wound Healing And Tissue Regeneration In Rats

Objectives

Novel α-bisabolol (BIS)-loaded citric acid cross-linked zein nanofibrous scaffolds (C-ZNFs) were proposed to serve as safe platforms for promoting wound repair in rats.

Methods

ZNFs were synthesized using electrospinning technique, then NFs, with adequate water resistance, were produced using citric acid as a safe cross-linker.

Results

Compared to the uncross-linked ZNFs, cross-linking with 7% w/w citric acid decreased swelling index by 3 folds, while the tensile strength and the contact angle were enhanced to 2.5 and 3.8 folds, respectively. SEM images showed beads-free homogeneous NFs with a fully inter-connected 3D-network, where the average diameter of optimized C-ZNFs was 181.7±50 nm. After 24 h, C-ZNFs exhibited a decreased BIS release rate (45.6%), compared to uncross-linked mats (84.9%). By increasing BIS concentration, the cell adhesion (WI38 fibroblasts) was improved which can be attributed mainly to BIS activation of transforming growth factor-beta (TGF-β1). The MTT-OD obtained values indicated that all tested zein scaffolds significantly enhanced the viability of WI38 fibroblasts, compared to the control after 48h of incubation which can be referred to the proliferative potential of zein by provoking cell spreading process. The scratch wound assay demonstrated that BIS-loaded ZNF scaffolds showed accelerated migration and proliferation of fibroblasts expressed by significantly higher wound closure rates compared to the control sample. BIS-loaded-C-ZNFs prominently accelerated tissue regeneration for wound closure demonstrated by entirely grown epithelium with normal keratinization and rapid wound contraction, compared to the control. Immunohistochemical results confirmed the superiority of BIS-loaded-C-ZNFs, where the observed reduced NF-κB and the elevated cytokeratin expressions confirmed the anti-inflammatory and proliferative effects of the scaffolds, respectively.

Conclusion

In-vitro, optimized C-ZNFs offered a satisfactory cytocompatibility, adhesion and healing which were consistent with the in-vivo results. BIS-loaded-C-ZNFs could be regarded as a promising and effective biomaterial for tissue regeneration and for accelerating the wound healing process.

Effect of the hyaluronic acid-poloxamer hydrogel on skin-wound healing: in vitro and in vivo studies

BACKGROUND

Recent research into skin injury and wound healing has focused mainly on post-trauma hemostasis, infection prevention, dermal regeneration and angiogenesis. However, less attention has been paid to air permeability and moisture loss prevention which also play important roles in injury healing.

METHODS

In the present work, we prepared a hyaluronic acid-poloxamer (HA-POL) hydrogel and tested the therapeutic effect of the hydrogel on skin-wound healing.

RESULTS

The HA-POL hydrogel transformed from sol to gel at 30°C, close to body temperature, and had stable moisturizing properties. HA-POL hydrogel promoted skin-wound healing and increased protein accumulation in the wound area. HA-POL hydrogel allowed greater air permeability than Band-aid, a typical wound covering. Results from transwell assays showed that the HA-POL hydrogel effectively isolated skin-wounds from bacterial invasion.

CONCLUSION

This work demonstrates the advantages of using HA-POL gel materials in the treatment of cutaneous wounds.

Sea bass (Lateolabrax maculatus) accelerates wound healing: A transition from inflammation to proliferation

ETHNOPHARMACOLOGICAL RELEVANCE

Sea bass (Lateolabrax maculatus) has been used for dietary therapy practice for wound healing of puerperal or surgery patients in China. Traditional Chinese medicinal books also documented that sea bass can be used to manage inflammation-associated conditions such as wound, miscarriage and cough. Some studies also proved that dietary supplement with fish benefited for treating many inflammatory - associated conditions, such as cardiovascular disease, ulcerative colitis and hyperlipidemia. However, the studies on the pharmacological mechanisms of wound healing efficacy of sea bass remain lack of investigation.

AIM OF THE STUDY

The aim of this study is to investigate the molecular mechanisms of sea bass on wound healing efficacy. Establishing a further justification for clinical application of aqueous extract of sea bass (ASB) in treating wound healing.

MATERIALS AND METHODS

Transition from inflammation to proliferation phase treated as the critical step in wound repair which were investigated via in vitro and in vivo study. A series of inflammatory mediators associated with wound healing and proliferation effects of fibroblasts upon treatments were studied via Western blotting, enzyme-linked immunosorbent assay (ELISA), real time reverse transcription-polymerase chain reaction (RT-PCR) and scratch assay. The cutaneous wound model was applied on skin wound healing study to observe the healing process in C57BL/6 mice upon ASB treatments. Hematological parameters and tumor necrosis factor-α (TNF-α) secretions in serum were determined. Histopathological examinations were conducted by hematoxylin and eosin (H&E) staining and Masson staining. Immunofluorescence were performed to identify infiltrating neutrophils (MPO) and α-smooth muscle actin (α-SMA).

RESULTS

Results showed that ASB significantly reduced the production of inflammatory mediators cyclooxygenase-2 (COX-2), nitrite oxide (NO) production and TNF-α. The phosphorylation and nuclear protein levels of transcription factor nuclear factor-κB (NF-ĸB) in toll-like receptor 4 (TLR4) signaling were decreased by ASB treatment as well. Wound closure rate and cyclin D1 expression level of fibroblasts were significantly increased by ASB treatments. Moreover, cutaneous wound model in C57BL/6 mice presented many similarities in appearance to the process of wound healing.

CONCLUSIONS

The in vitro study demonstrated an inhibitory effect of ASB on the inflammatory mediators regulated by TLR4 signaling pathways, providing evidence that ASB treatment potentially accelerate the wound healing through migration and proliferation enhancement. Additionally, the in vivo study suggested that ASB treatment has a potential in accelerating the proliferation phase of wound healing via well-organized abundant collagen deposition, angiogenesis and re-epithelialization in wounds. The present findings can be treated as a pharmacological basis for the folk use of sea bass and further studies in biological and medical fields.

Aster koraiensis extract improves impaired skin wound healing during hyperglycemia

Background

Diabetes mellitus (DM) is one of the most common diseases found across the world. Aster koraiensis extract (AKE) has a protective effect on diabetic complications such as diabetic retinopathy. However, the effects of AKE on hyperglycemia-linked impairment of wound healing during DM have not been elucidated. In this study, we investigated the effects of AKE on delayed wound healing induced by DM.

Methods

DM was induced by intraperitoneal administration of streptozotocin (STZ; 75 mg/kg) to Sprague Dawley (SD) rats. Next, a wound was induced on the back of rats after administration of STZ. Further, AKE was prepared using an alcoholic extraction of A. koraiensis and orally administered daily for 18 days. Wound healing was evaluated using an in vitro migration assay and measuring the wound area in vivo. Skin tissue thickness was evaluated using hematoxylin and eosin staining. Matrix metalloprotease (MMP) activity and expression were detected using zymography and immunohistochemistry.

Results

AKE administration improved the delayed migration of keratinocytes in hyperglycemic animals. It also attenuated an increase in keratinocyte MMP-2/9 activity induced by hyperglycemia. AKE protected against DM-induced impaired wound healing in rats and prevented the degradation of skin tissue induced by DM. In addition, AKE attenuated DM-induced increase in MMP-2/9 expression in skin tissue.

Conclusions

In conclusion, AKE may promote wound healing by re-epithelization via promotion of keratinocyte migration and by attenuating the disruption of the skin tissue layer via MMP-2/9 inhibition during hyperglycemia.