Naturally-derived targeted therapy for wound healing: Beyond classical strategies

A Nanocomposite Dynamic Covalent Cross-Linked Hydrogel Loaded with Fusidic Acid for Treating Antibiotic-Resistant Infected Wounds

Methicillin-resistant Staphylococcus aureus (MRSA) is associated with high levels of morbidity and is considered a difficult-to-treat infection, often requiring nonstandard treatment regimens and antibiotics. Since over 40% of the emerging antibiotic compounds have insufficient solubility that limits their bioavailability and thus efficacy through oral or intravenous administration, it is crucial that alternative drug delivery products be developed for wound care applications. Existing effective treatments for soft tissue MRSA infections, such as fusidic acid (FA), which is typically administered orally, could also benefit from alternative routes of administration to improve local efficacy and bioavailability while reducing the required therapeutic dose. Herein, we report an antimicrobial poly(oligoethylene glycol methacrylate) (POEGMA)-based composite hydrogel loaded with fusidic acid-encapsulating self-assembled polylactic acid-b-poly(oligo(ethylene glycol) methyl ether methacrylate) (PLA-POEGMA) nanoparticles for the treatment of MRSA-infected skin wounds. The inclusion of the self-assembled nanoparticles (380 nm diameter when loaded with fusidic acid) does not alter the favorable mechanical properties and stability of the hydrogel in the context of its use as a wound dressing, while fusidic acid (FA) can be released from the hydrogel over ∼10 h via a diffusion-controlled mechanism. The antimicrobial studies demonstrate a clear zone of inhibition in vitro and a 1-2 order of magnitude inhibition of bacterial growth in vivo in an MRSA-infected full-thickness excisional murine wound model even at very low antibiotic doses. Our approach thus can both circumvent challenges in the local delivery of hydrophobic antimicrobial compounds and directly deliver antimicrobials into the wound to effectively combat methicillin-resistant infections using a fraction of the drug dose required using other clinically relevant strategies.

Hesperidin-loaded cubogel as a novel therapeutic armamentarium for full-thickness wound healing

Wounds are a physical manifestation of injury to the skin causing it to rupture or tear. The process of wound healing naturally restores skin integrity while minimizing the extent of the damage. Hesperidin (HPN) is a natural polyphenolic flavonoid and is effective in treating wounds due to its ability to reduce inflammation and stimulate angiogenesis. However, its use is limited by its poor physicochemical attributes such as poor solubility in water. Recently, nanoparticles, particularly Cubosomes, are found to be promising candidates for advancing wound-healing therapies, owing to their unique properties. The present study was conducted to develop a hydrogel system based on Cubosomes encapsulating HPN (HPN-Cubogel), with the potential to mitigate full-thickness wounds. The therapeutic efficacy of the formulation assessed in the animal model showed that the HPN-Cubogel formulation group exhibited a wound closure rate of 98.96 ± 1.50% after 14 days post-wounding compared to 89.12 ± 2.6% in the control group suggesting superior wound contraction activity. Collagen synthesis was superior in the formulation compared to the control group, as determined through MT staining. In summary, the HPN-Cubogel formulation was found to be the most effective in enhancing full-thickness wound healing.

Pyrogallol loaded chitosan-based polymeric hydrogel for controlling Acinetobacter baumannii wound infections: Synthesis, characterization, and topical application

Antibacterial hydrogels have emerged as a promising approach for wound healing, owing to their ability to integrate antibacterial agents into the hydrogel matrix. Benefiting from its remarkable antibacterial and wound-healing attributes, pyrogallol has been introduced into chitosan-gelatin for the inaugural development of an innovative antibacterial polymeric hydrogel tailored for applications in wound healing. Hence, we observed the effectiveness of pyrogallol in inhibiting the growth of A. baumannii, disrupting mature biofilms, and showcasing robust antioxidant activity both in vitro and in vivo. In addition, pyrogallol promoted the migration of human epidermal keratinocytes and exhibited wound healing activity in zebrafish. These findings suggest that pyrogallol holds promise as a therapeutic agent for wound healing. Interestingly, the pyrogallol-loaded chitosan-gelatin (Pyro-CG) hydrogel exhibited enhanced mechanical strength, stability, controlled drug release, biodegradability, antibacterial activity, and biocompatibility. In vivo results established that Pyro-CG hydrogel promotes wound closure and re-epithelialization in A. baumannii-induced wounds in molly fish. Therefore, the prepared Pyro-CG polymeric hydrogel stands poised as a potent and promising agent for wound healing with antibacterial properties. This holds considerable promise for the development of effective therapeutic interventions to address the increasing menace of A. baumannii-induced wound infections.

Development and optimization of film forming non-pressurized liquid bandage for wound healing by Box-Behnken statistical design

The goal of the current investigation was to develop a non-pressurized liquid bandage to promote the healing of wounds by using silver sulfadiazine. A three-factor three level box-behnken statistical design was employed to optimize the drug-loaded liquid bandage. Film-forming liquid bandage was developed by using ethyl-cellulose, dibutyl sebacate, and glycerol. For optimization, ethyl cellulose, dibutyl sebacate, and isopropyl myristate were taken as independent variables while tensile strength, water vapor absorption value, and drying time were taken as dependent variables. The film-forming liquid bandage was evaluated for various parameters like tensile strength, water vapor absorption value, drying time, viscosity, pH, in-vitro drug release studies, in-vivo wound healing studies, and stability studies. The optimized formulation was found with the tensile strength of 68.24 ± 0.24 MPa, water vapor absorption value of 2.00 ± 0.25 %, drying time of 1.75 ± 0.14 min, viscosity of 60 ± 0.5 cPs, pH of 6.0 ± 0.5 and good physicochemical properties with satisfactory film-forming ability. The in-vitro study shows that the release of test formulations was better than the marketed formulation. After 6 h of study, the liquid bandage and marketed formulation showed 41.02 % and 29.32 % of drug release respectively. Significant results were obtained for the in-vivo wound healing studies. Upon comparison with the control group (2.61 mm) and marketed formulation (1.44 mm), rats treated with the optimized formulation exhibited a noticeable improvement in wound contraction (0.8 mm). The liquid bandage after three months of stability testing was found to be stable with optimum. The film-forming liquid bandage was found to be an effective alternative to conventional topical preparations as it develops a thin polymeric layer on the wound and the skin around it and improves comfort for the patient by protecting the wound from external factors and physical harm.

Hepatoprotective effects of a chemically-characterized extract from artichoke (Cynara scolymus L.) against AFB1-induced toxicity in rats

This study was conducted to investigate the protective potential of a pharmaceutically formulated capsule of artichoke leaf powder (ArLP) against aflatoxin B1 (AFB1)-induced hepatotoxicity in male albino rats. In the 42-day experiment, rats were divided into five equal groups: (i) control, treated with sterile water, (ii) treated with 4% DMSO as AFB1 vehicle, (iii) ArLP of 100 mg kg-1 bw, (iv) AFB1 of 72 µg kg-1 bw, and (v) AFB1 plus ArLP. Exposure of rats to AFB1 resulted in hepatotoxicity as manifested by the intensification of oxidative stress, production of free radicals and significant increase in the activity levels of liver function enzymes relative to the control. Significant reductions in both the enzymatic and non-enzymatic antioxidant markers as well as histopathological abnormalities in liver tissues were also observed. Notably, the combined administration of ArLP with AFB1 clearly reduced AFB1-mediated adverse effects leading to the normalization of most of these parameters back to control levels. These findings clearly highlight the potential benefits of artichoke dietary supplements as a safe and natural solution in counteracting the adverse hepatotoxic effects conferred by AFB1 exposure. Further research is warranted to fully dissect the biochemical and molecular mechanism of action of the observed artichoke-mediated hepatoprotection.

Potential of nanoemulsions for accelerated wound healing: innovative strategies

Wounds represent various significant health concerns for patients and also contribute major costs to healthcare systems. Wound healing comprises of overlapped and various coordinated steps such as homeostasis, inflammation, proliferation, and remodeling. In response to the failure of many strategies in delivering intended results including wound closure, fluid loss control, and exhibiting properties such as durability, targeted delivery, accelerated action, along with histocompatibility, numerous nanotechnological advances have been introduced. To understand the magnitude of wound therapy, this systematic and updated review discussing the effectiveness of nanoemulsions has been undertaken. This review portrays mechanisms associated with wound healing, factors for delayed wound healing, and various technologies utilized to treat wounds effectively. While many strategies are available, nanoemulsions have attracted the tremendous attention of scientists globally for the research in wound therapy due to their long-term thermodynamic stability and bioavailability. Nanoemulsions not only aid in tissue repair, but are also considered as an excellent delivery system for various synthetic and natural actives. Nanotechnology provides several pivotal benefits in wound healing, including improved skin permeation, controlled release, and stimulation of fibroblast cell proliferation. The significant role of nanoemulsions in improved wound healing along with their preparation techniques has also been highlighted with special emphasis on mechanistic insights. This article illustrates recent research advancements for the utilization of nanoemulsions in wound treatment. An adequate literature search has been conducted using the keywords 'Nanoemulsions in wound healing', 'Wound therapy and nanoemulsions', 'Herbal actives in wound therapy', 'Natural oils and wounds treatment' etc., from PubMed, Science Direct, and Google Scholar databases. Referred and original publications in the English language accessed till April 2022 has been included, whereas nonEnglish language papers, unpublished data, and nonoriginal papers were excluded from the study.

Manuka honey activates the aryl hydrocarbon receptor: Implications for skin inflammation

Manuka honey (MH) is a complex nutritional material with antimicrobial, antioxidant and anti-inflammatory activity. We have previously shown that MH down regulates IL-4-induced CCL26 expression in immortalized keratinocytes. As MH contains potential ligands of the Aryl Hydrocarbon Receptor (AHR), a key regulator of skin homeostasis, we hypothesize that this effect is mediated via AHR activation. Here, we treated HaCaT cell lines, either stable transfected with an empty vector (EV-HaCaT) or in which AHR had been stable silenced (AHR-silenced HaCaT); or primary normal human epithelial keratinocytes (NHEK) with 2% MH for 24 h. This induced a 15.4-fold upregulation of CYP1A1 in EV-HaCaTs, which was significantly reduced in AHR-silenced cells. Pre-treatment with the AHR antagonist CH223191 completely abrogated this effect. Similar findings were observed in NHEK. In vivo treatment of the Cyp1a1Cre x R26ReYFP reporter mice strain's skin with pure MH significantly induced CYP1A1 expression compared with Vaseline. Treatment of HaCaT with 2% MH significantly decreased baseline CYP1 enzymatic activity at 3 and 6 h but increased it after 12 h, suggesting that MH may activate the AHR both through direct and indirect means. Importantly, MH downregulation of IL-4-induced CCL26 mRNA and protein was abrogated in AHR-silenced HaCaTs and by pre-treatment with CH223191. Finally, MH significantly upregulated FLG expression in NHEK in an AHR-dependent manner. In conclusion, MH activates AHR, both in vitro and in vivo, thereby providing a mechanism of its IL4-induced CCL26 downregulation and upregulation of FLG expression. These results have potential clinical implications for atopic diseases and beyond.

A Case of Gangrenous Herpes Zoster Complicated with Candida albicans Infection

Background

Herpes zoster is a disease caused by varicella-zoster virus infection, which is characterized by dense clusters of vesicles distributed along unilateral bands of nerves and accompanied by neuralgia. Although the disease is self-limited, some patients may develop neurological, ocular, skin, or visceral complications.

Case Presentation

We report a 65-year-old Chinese man with ulceration secondary to cutaneous blister rupture on the left lumbar abdomen, who was diagnosed with herpes zoster and did not respond to conventional treatment. Dermatological examination showed diffuse dark erythema with clear boundaries on his left waist and abdomen. Deep ulcers of different sizes were densely distributed with steep edges and relatively dry base, while yellow secretions and black scabs could be seen. Fungal microscopy showed a few pseudohyphae and clusters of spores. Meanwhile, the fungal culture of the secretions showed Candida albicans growth. Skin biopsy of the affected skin from the ulcer of the left abdomen revealed epidermal absence and clusters of spores in the superficial dermis. PAS staining was positive. The patient was diagnosed with gangrenous herpes zoster complicated with Candida albicans infection. After antifungal treatment based on the results of drug sensitivity, the patient's condition was improved.

Conclusion

This case reveals the co-existence of herpes zoster and Candida albicans infection, expands our understanding of overlapping diseases, and provides value for clinical diagnosis and treatment.

Aloe vera-Based Hydrogels for Wound Healing: Properties and Therapeutic Effects

Aloe vera-based hydrogels have emerged as promising platforms for the delivery of therapeutic agents in wound dressings due to their biocompatibility and unique wound-healing properties. The present study provides a comprehensive overview of recent advances in the application of Aloe vera-based hydrogels for wound healing. The synthesis methods, structural characteristics, and properties of Aloe vera-based hydrogels are discussed. Mechanisms of therapeutic agents released from Aloe vera-based hydrogels, including diffusion, swelling, and degradation, are also analyzed. In addition, the therapeutic effects of Aloe vera-based hydrogels on wound healing, as well as the reduction of inflammation, antimicrobial activity, and tissue regeneration, are highlighted. The incorporation of various therapeutic agents, such as antimicrobial and anti-inflammatory ones, into Aloe vera-based hydrogels is reviewed in detail. Furthermore, challenges and future prospects of Aloe vera-based hydrogels for wound dressing applications are considered. This review provides valuable information on the current status of Aloe vera-based hydrogels for the delivery of therapeutic agents in wound dressings and highlights their potential to improve wound healing outcomes.

Natural exosome-like nanoparticles derived from ancient medicinal insect Periplaneta americana L. as a novel diabetic wound healing accelerator

Along with the recognized therapeutic outcomes of regenerative medicine, extracellular vesicles and their exosome subsets have become an alternative option for wound healing. Periplaneta americana L. (PA), an ancient and traditional medicinal insect, has been around for 300 million years, and displays magic formidable vitality and environmental adaptive ability. The linkage between intrinsic amputation regeneration feature and the acknowledged wound healing medicinal benefit of PA has never been revealed. Herein, inspired by the ability of exosomes to participate in the interkingdom communication, we explored whether this effect was ascribed to PA derived exosome-like nanoparticles (PA-ELNs). PA-ELNs were extracted by differential velocity centrifugation approach and characterized by DLS, NTA and TEM. Their cargoes were analyzed by LC-MS/MS proteomics and small RNA-seq analysis. The wound healing activity was verified in vivo and in vitro. PA-ELNs with a concentration of 2.33x10⁹±6.35x10⁷ particles/mL exhibited a lipid bilayer-bound membrane structure with an average size of 104.7 nm. Furthermore, the miRNA cargoes in PA-ELNs participate in some wound healing related signal pathways such as TGF-beta, mTOR, and autophagy. As expected, the in vitro tests indicated that PA-ELNs were apt to be internalized in HUVECs, L929 and RAW 264.7 cells and contributed to cell proliferation and migration. Most importantly, we demonstrated that the topical administration of PA-ELNs could remarkably accelerate wound healing in a diabetic mouse model, and was involved in anti-inflammatory, re-epithelialization and autophagy regulation. This study provides clear evidence for the first time that PA-ELNs, as diabetic wound healing accelerators, are the "bioactive code" of this ancient medicinal insect.

Unravelling the potential of insects for medicinal purposes - A comprehensive review

Entomotherapy, the use of insects for medicinal purposes, has been practised for centuries in many countries around the world. More than 2100 edible insect species are eaten by humans, but little is known about the possibility of using these insects as a promising alternative to traditional pharmaceuticals for treating diseases. This review offers a fundamental understanding of the therapeutic applications of insects and how they might be used in medicine. In this review, 235 insect species from 15 orders are reported to be used as medicine. Hymenoptera contains the largest medicinal insect species, followed by Coleoptera, Orthoptera, Lepidoptera, and Blattodea. Scientists have examined and validated the potential uses of insects along with their products and by-products in treating various diseases, and records show that they are primarily used to treat digestive and skin disorders. Insects are known to be rich sources of bioactive compounds, explaining their therapeutic features such as anti-inflammatory, antimicrobial, antiviral, and so on. Challenges associated with the consumption of insects (entomophagy) and their therapeutic uses include regulation barriers and consumer acceptance. Moreover, the overexploitation of medicinal insects in their natural habitat has led to a population crisis, thus necessitating the investigation and development of their mass-rearing procedure. Lastly, this review suggests potential directions for developing insects used in medicine and offers advice for scientists interested in entomotherapy. In future, entomotherapy may become a sustainable and cost-effective solution for treating various ailments and has the potential to revolutionize modern medicine.

Switchable hepatic organelles aberrations in DEN-induced mice under the influence of chemically characterized silk sericin

OBJECTIVE

Assessing the beneficial effects of silk sericin against hepatic injury induced by diethylnitrosamine (DEN).

METHODS

Aiming at promoting sericin as a natural product able to counteract the hazards of toxic elements, HPLC profile was conducted on the extracted sericin sample versus the standard one to qualitatively identify it. Following sericin treatment on human HepG2 liver cancer cells, many parameters were analyzed in vitro including cell viability, cell cycle, and cell apoptosis. Hepatic pro-inflammatory cytokines as well as histopathological and ultrastructure changes were evaluated in vivo in the different experimental groups.

RESULTS

Sericin exhibited a dose-dependent cytotoxic effect on HepG2 cells with an IC50 of 14.12 + 0.75 μg/mL. The hepatotoxicity of DEN was manifested in mice by increased pro-inflammatory markers (IL-2, IL-6, and TNF-α), decreased IL-10, liver structure deterioration, and characteristic histopathological and ultrastructure changes. Sericin administration reversed most of the observed alterations inflected by DEN.

CONCLUSIONS

Our results substantiate the sericin's powerful apoptotic impact in vitro. In experimental mice, combination treatment using sericin together with melatonin appears to be more potent in mitigating the adverse effects of DEN. However, further investigations are needed to identify the underlying mechanism of action and complement the knowledge about the expected medicinal values of sericin.

Self-Homeostasis Immunoregulatory Strategy for Implant-Related Infections through Remodeling Redox Balance

Implant-related infections (IRIs) are catastrophic complications after orthopedic surgery. Excess reactive oxygen species (ROS) accumulated in IRIs create a redox-imbalanced microenvironment around the implant, which severely limits the curing of IRIs by inducing biofilm formation and immune disorders. However, current therapeutic strategies commonly eliminate infection utilizing the explosive generation of ROS, which exacerbates the redox imbalance, aggravating immune disorders and promoting infection chronicity. Herein, a self-homeostasis immunoregulatory strategy based on a luteolin (Lut)-loaded copper (Cu²⁺)-doped hollow mesoporous organosilica nanoparticle system (Lut@Cu-HN) is designed to cure IRIs by remodeling the redox balance. In the acidic infection environment, Lut@Cu-HN is continuously degraded to release Lut and Cu²⁺. As both an antibacterial and immunomodulatory agent, Cu²⁺ kills bacteria directly and promotes macrophage pro-inflammatory phenotype polarization to activate the antibacterial immune response. Simultaneously, Lut scavenges excessive ROS to prevent the Cu²⁺-exacerbated redox imbalance from impairing macrophage activity and function, thus reducing Cu²⁺ immunotoxicity. The synergistic effect of Lut and Cu²⁺ confers excellent antibacterial and immunomodulatory properties to Lut@Cu-HN. As demonstrated in vitro and in vivo, Lut@Cu-HN self-regulates immune homeostasis through redox balance remodeling, ultimately facilitating IRI eradication and tissue regeneration.

Heparin-based sericin hydrogel-encapsulated basic fibroblast growth factor for in vitro and in vivo skin repair

The treatment of full-thickness cutaneous wounds remains a significant challenge in clinical therapeutics. Exogenous growth factor (GF) has been applied in clinics to promote wound healing. However, the retention of GF on the wound bed after its direct application to the wound surface is difficult. Moreover, growth factors (GFs) are always inactivated in the complex wound healing microenvironment due to various factors, which significantly decrease the therapeutic effect. Sericin hydrogel (S) can be used as an effective carrier for GFs owing to its low immunogenicity, good biocompatibility, and good healing-promoting ability. Here, we designed a heparin-based sericin hydrogel (HS) -encapsulated basic fibroblast growth factor (bFGF-HS) to facilitate wound healing and skin regeneration. The hydrogel exhibited a three-dimensional (3D) microporous structure, excellent biodegradability, good adhesiveness, and low cytotoxicity. In vitro release of bFGF from bFGF-HS coacervates revealed that bFGF-HS might control the release of bFGF within 25 days through heparin regulation. bFGF-HS significantly promoted vascularization and re-epithelialization and improved collagen deposition, ultimately accelerating wound healing in vivo in mice. bFGF-HS treated wounds were also found to have more hair follicles and milder inflammatory reactions. Overall, this study provides a new therapeutic approach for full-thickness skin defect wounds using bFGF-HS.

Targeting matrix metalloproteases in diabetic wound healing

Chronic inflammation participates in the progression of multiple chronic diseases, including obesity, diabetes mellitus (DM), and DM related complications. Diabetic ulcer, characterized by chronic wounds that are recalcitrant to healing, is a serious complication of DM tremendously affecting the quality of life of patients and imposing a costly medical burden on society. Matrix metalloproteases (MMPs) are a family of zinc endopeptidases with the capacity of degrading all the components of the extracellular matrix, which play a pivotal part in healing process under various conditions including DM. During diabetic wound healing, the dynamic changes of MMPs in the serum, skin tissues, and wound fluid of patients are in connection with the degree of wound recovery, suggesting that MMPs can function as essential biomarkers for the diagnosis of diabetic ulcer. MMPs participate in various biological processes relevant to diabetic ulcer, such as ECM secretion, granulation tissue configuration, angiogenesis, collagen growth, re-epithelization, inflammatory response, as well as oxidative stress, thus, seeking and developing agents targeting MMPs has emerged as a potential way to treat diabetic ulcer. Natural products especially flavonoids, polysaccharides, alkaloids, polypeptides, and estrogens extracted from herbs, vegetables, as well as animals that have been extensively illustrated to treat diabetic ulcer through targeting MMPs-mediated signaling pathways, are discussed in this review and may contribute to the development of functional foods or drug candidates for diabetic ulcer therapy. This review highlights the regulation of MMPs in diabetic wound healing, and the potential therapeutic ability of natural products for diabetic wound healing by targeting MMPs.

Synthesis and Characterization of Curcumin-Chitosan Loaded Gold Nanoparticles by Oryctes rhinoceros' Chitin for Cosmeceutical Application

A breakthrough in cosmeceuticals by utilizing insects as major ingredients in cosmetic products is gaining popularity. Therefore, the interest in rare sources of ingredients, for instance, from the Oryctes rhinoceros beetle, can bring huge benefits in terms of turning pests into wealth. In this study, curcumin was chosen as the active ingredient loaded into chitosan-gold nanoparticles (CCG-NP). Curcumin is unstable and has poor absorption, a high rate of metabolism, and high sensitivity to light. These are all factors that contribute to the low bioavailability of any substance to reach the target cells. Therefore, chitosan extracted from O. rhinoceros could be used as a drug carrier to overcome these limitations. In order to overcome these limitations, CCG-NPs were synthesized and characterized. Chitosan was isolated from O. rhinoceros and CCG-NPs were successfully synthesized at 70 °C for 60 min under optimal conditions of a reactant ratio of 2:0.5 (0.5 mM HAuCl₄: 0.1% curcumin). Characterizations of CCG-NP involved FTIR analysis, zeta potential, morphological properties determination by FE-SEM, particle size analysis, crystallinity study by XRD, and elemental analysis by EDX. The shape of the CCG-NP was round, its size was 128.27 d.nm, and the value of the zeta potential was 20.2 ± 3.81 mV. The IC50 value for cell viability is 58%, indicating a mild toxicity trait. To conclude, CCG-NP is a stable, spherical, nano-sized, non-toxic, and homogeneous solution.

Current Progress and Outlook of Nano-Based Hydrogel Dressings for Wound Healing

Wound dressing is an important tool for wound management. Designing wound dressings by combining various novel materials and drugs to optimize the peri-wound environment and promote wound healing is a novel concept. Hydrogels feature good ductility, high water content, and favorable oxygen transport, which makes them become some of the most promising materials for wound dressings. In addition, nanomaterials exhibit superior biodegradability, biocompatibility, and colloidal stability in wound healing and can play a role in promoting healing through their nanoscale properties or as carriers of other drugs. By combining the advantages of both technologies, several outstanding and efficient wound dressings have been developed. In this paper, we classify nano-based hydrogel dressings into four categories: hydrogel dressings loaded with a nanoantibacterial drug; hydrogel dressings loaded with oxygen-delivering nanomedicines; hydrogel dressings loaded with nanonucleic acid drugs; and hydrogel dressings loaded with other nanodelivered drugs. The design ideas, advantages, and challenges of these nano-based hydrogel wound dressings are reviewed and analyzed. Finally, we envisaged possible future directions for wound dressings in the context of relevant scientific and technological advances, which we hope will inform further research in wound management.

The wound healing effect of collagen/adipose-derived stem cells (ADSCs) hydrogel: In vivo study

BACKGROUND

The complex wound healing process involves activating and synchronizing intracellular, intercellular, and extracellular components. Adipose tissue is attracting attention to promote wound healing. Within subcutaneous adipose tissue, stromal vascular cells and their subsets release growth factors and cytokines critical for neovascularization and wound repair.

OBJECTIVES

This study evaluated human placental collagen/adipose-derived stem cells (ADSCs) hydrogel for wound healing in rats.

METHODS

In this study, ADSCs were harvested, cultured, and mixed with placental collagen. Twelve rats were used, and their backs were excised three times each. Group one received collagen/ADSCs, group two collagen, and group three non-filled (control) excisions. The healing processes were assessed by histological analysis, taking photographs, and calculating the percentage of wound contraction in mentioned times.

RESULTS

Histopathological analysis revealed that the content of fibroblasts, follicles of the hair, and angiogenesis in group one was significantly more than in other groups. Group one had a significant result compared with the collagen and control groups. In group one, significant wound healing and wound contraction were observed with 52% and 80% wound contraction at 7 and 14 days, respectively.

CONCLUSION

Collagen/ADSCs can be considered a suitable candidate hydrogel in wound healing with a high potential for enhancing wound repairing.

In Vitro and In Vivo Characterization Methods for Evaluation of Modern Wound Dressings

Chronic wound management represents a major challenge in the healthcare sector owing to its delayed wound-healing process progression and huge financial burden. In this regard, wound dressings provide an appropriate platform for facilitating wound healing for several decades. However, adherent traditional wound dressings do not provide effective wound healing for highly exudating chronic wounds and need the development of newer and innovative wound dressings to facilitate accelerated wound healing. In addition, these dressings need frequent changing, resulting in more pain and discomfort. In order to overcome these issues, a wide range of affordable and innovative modern wound dressings have been developed and explored recently to accelerate and improve the wound healing process. However, a comprehensive understanding of various in vitro and in vivo characterization methods being utilized for the evaluation of different modern wound dressings is lacking. In this context, an overview of modern dressings and their complete in vitro and in vivo characterization methods for wound healing assessment is provided in this review. Herein, various emerging modern wound dressings with advantages and challenges have also been reviewed. Furthermore, different in vitro wound healing assays and in vivo wound models being utilized for the evaluation of wound healing progression and wound healing rate using wound dressings are discussed in detail. Finally, a summary of modern wound dressings with challenges and the future outlook is highlighted.

Antibacterial Efficacy and Healing Potential of Honey from Different Zones in Nigeria on Diabetic-Induced Wound Infection in Wistar Rats

There is an increase in drug-resistant strains causing infection, thus making available therapeutics less effective. As resistance increases, modern medicine focuses on the antibacterial potential of natural products, which can aid in wound healing. The present study determined Nigeria honey's antibacterial efficacy in treating diabetes-induced wound infections in Wistar albino rats. 54 Wistar rats randomly divided into 9 groups of 6 each were used for the study: group I (negative control, no treatment), group II (positive control, diabetes without treatment), group III (diabetes treated with 1% silver sulfadiazine), and groups IV–IX (diabetes treated with different honey samples). Physiochemical analysis and microbiological and antibacterial activity of the honey samples were determined. The treatments were carried out for 17 days, and wound contraction, malondialdehyde (MDA) levels, and catalase activity were measured. Results obtained showed that the most effective honey was DCH (21.5 ± 2.12), followed by HBP + M (15 ± 2.12) and TRB, JS, and HBP (13 ± 2.8; 13 ± 1.41; 13.5 ± 0.71) for antibacterial activity on Staphylococcus aureus. Microbiologically, no coliform was detected in all the samples, confirming the honey's quality. The amount of lipid peroxidation was raised in the diabetic group with no treatment, 1% silver sulfadiazine group, and JS group, while no significant reduction was observed in other groups. Differences in wound contraction were significantly notable on various days of measurement, day 3 (p < 0.002), day 6 (p < 0.046), and day 9 (p = 0.00). The catalase level in the different treatment groups increased significantly (p < 0.05), implying an antioxidant potential of the different honey samples except for Jos honey. The study concludes that honey infused with moringa was faster and more efficient in healing diabetic wounds than other honey samples and silver sulfadiazine.

Mechanistic Wound Healing and Antioxidant Potential of Moringa oleifera Seeds Extract Supported by Metabolic Profiling, In Silico Network Design, Molecular Docking, and In Vivo Studies

Moringa oleifera Lam. (Moringaceae) is an adaptable plant with promising phytoconstituents, interesting medicinal uses, and nutritional importance. Chemical profiling of M. oleifera seeds assisted by LC-HRMS (HPLC system coupled to a high resolution mass detector) led to the dereplication of 19 metabolites. Additionally, the wound healing potential of M. oleifera seed extract was investigated in male New Zealand Dutch strain albino rabbits and supported by histopathological examinations. Moreover, the molecular mechanisms were investigated via different in vitro investigations and through analyzing the relative gene and protein expression patterns. When compared to the untreated and MEBO®-treated groups, topical administration of M. oleifera extract on excision wounds resulted in a substantial increase in wound healing rate (p < 0.001), elevating TGF-β1, VEGF, Type I collagen relative expression, and reducing inflammatory markers such as IL-1β and TNF-α. In vitro antioxidant assays showed that the extract displayed strong scavenging effects to peroxides and superoxide free radicals. In silico studies using a molecular docking approach against TNF-α, TGFBR1, and IL-1β showed that some metabolites in M. oleifera seed extract can bind to the active sites of three wound-healing related proteins. Protein−protein interaction (PPI) and compound−protein interaction (CPI) networks were constructed as well. Quercetin, caffeic acid, and kaempferol showed the highest connectivity with the putative proteins. In silico drug likeness studies revealed that almost all compounds comply with both Lipinski’s and Veber’s rule. According to the previous findings, an in vitro study was carried out on the pure compounds, including quercetin, kaempferol, and caffeic acid (identified from M. oleifera) to validate the proposed approach and to verify their potential effectiveness. Their inhibitory potential was evaluated against the pro-inflammatory cytokine IL-6 and against the endopeptidase MMPs (matrix metalloproteinases) subtype I and II, with highest activity being observed for kaempferol. Hence, M. oleifera seeds could be a promising source of bioactive compounds with potential antioxidant and wound healing capabilities.

Innovative Treatment Strategies to Accelerate Wound Healing: Trajectory and Recent Advancements

Wound healing is highly specialized dynamic multiple phase process for the repair of damaged/injured tissues through an intricate mechanism. Any failure in the normal wound healing process results in abnormal scar formation, and chronic state which is more susceptible to infections. Chronic wounds affect patients’ quality of life along with increased morbidity and mortality and are huge financial burden to healthcare systems worldwide, and thus requires specialized biomedical intensive treatment for its management. The clinical assessment and management of chronic wounds remains challenging despite the development of various therapeutic regimens owing to its painstakingly long-term treatment requirement and complex wound healing mechanism. Various conventional approaches such as cell therapy, gene therapy, growth factor delivery, wound dressings, and skin grafts etc., are being utilized for promoting wound healing in different types of wounds. However, all these abovementioned therapies are not satisfactory for all wound types, therefore, there is an urgent demand for the development of competitive therapies. Therefore, there is a pertinent requirement to develop newer and innovative treatment modalities for multipart therapeutic regimens for chronic wounds. Recent developments in advanced wound care technology includes nanotherapeutics, stem cells therapy, bioengineered skin grafts, and 3D bioprinting-based strategies for improving therapeutic outcomes with a focus on skin regeneration with minimal side effects. The main objective of this review is to provide an updated overview of progress in therapeutic options in chronic wounds healing and management over the years using next generation innovative approaches. Herein, we have discussed the skin function and anatomy, wounds and wound healing processes, followed by conventional treatment modalities for wound healing and skin regeneration. Furthermore, various emerging and innovative strategies for promoting quality wound healing such as nanotherapeutics, stem cells therapy, 3D bioprinted skin, extracellular matrix-based approaches, platelet-rich plasma-based approaches, and cold plasma treatment therapy have been discussed with their benefits and shortcomings. Finally, challenges of these innovative strategies are reviewed with a note on future prospects.

Recent Advances in Nano-Formulations for Skin Wound Repair Applications

Skin injuries caused by accidents and acute or chronic diseases place a heavy burden on patients and health care systems. Current treatments mainly depend on preventing infection, debridement, and hemostasis and on supplementing growth factors, but patients will still have scar tissue proliferation or difficulty healing and other problems after treatment. Conventional treatment usually focuses on a single factor or process of wound repair and often ignores the influence of the wound pathological microenvironment on the final healing effect. Therefore, it is of substantial research value to develop multifunctional therapeutic methods that can actively regulate the wound microenvironment and reduce the oxidative stress level at the wound site to promote the repair of skin wounds. In recent years, various bioactive nanomaterials have shown great potential in tissue repair and regeneration due to their properties, including their unique surface interface effect, small size effect, enzyme activity and quantum effect. This review summarizes the mechanisms underlying skin wound repair and the defects in traditional treatment methods. We focus on analyzing the advantages of different types of nanomaterials and comment on their toxicity and side effects when used for skin wound repair.

Artichoke Leaf Extract-Mediated Neuroprotection against Effects of Aflatoxin in Male Rats

Attenuation of adverse effects of aflatoxin (AFB₁) in brains of B₁ rats by extracts of leaves of artichoke was studied. The active ingredients in extracts of leaves of artichoke, Cynara scolymus L., were determined by HPLC analysis. In the 42-day experiment, rats were exposed to either sterile water, 4% DMSO, 100 mg artichoke leaf extract/kg body mass, 72 μg aflatoxin B₁/kg body mass, or AFB₁ plus artichoke leaf extract. Neurotoxicity of AFB₁ was determined by an increase in profile of lipids, augmentation of plasmatic glucose and concentrations of insulin, oxidative stress, increased activities of cholinergic enzymes, and a decrease in activities of several antioxidant enzymes and pathological changes in brain tissue. Extracts of artichoke leaf significantly reduced adverse effects caused by AFB₁, rescuing most of the parameters to values similar to unexposed controls, which demonstrated that adverse, neurotoxic effects caused by aflatoxin B₁ could be significantly reduced by simultaneous dietary supplementation with artichoke leaf extract, which itself is not toxic.

Wound-Healing Promotion and Anti-Inflammatory Properties of Carvacrol Prodrugs/Hyaluronic Acid Formulations

Background. Wound healing (WH) is a complex process involving several stages, such as hemostasis, inflammation, re-epithelialization, and remodeling. Many factors can impair WH, and different pharmacological approaches were studied to date, but the increase in antibiotic resistance, invasiveness, treatment duration, and high cost, have often hampered the resolution of the wound. In this study, we investigated the possible application of water-soluble carvacrol prodrugs (WSCPs) and hyaluronic acid (HA) and their formulations (WSCPs/HA) to improve WH and regulate the inflammatory response. Materials and methods. Firstly, the cytotoxicity of 0.1, 1 and 10 µg/mL of HA, WSCPs and WSCPs/HA formulations were evaluated on HaCaT cells and THP-1 cell lines. The ability of WSCPs/HA formulations to modulate wound repair was evaluated in an in vitro model of WH, using HaCaT cells at 6, 18, and 24 h. The expression of WH mediators, after wound closure was determined by qRT-PCR. Following, we polarized THP-1 cells in M1/M2-like macrophages and tested the anti-inflammatory properties of WSCPs/HA formulations. After, we tested the in vitro WH model for the effects of conditioned medium (CM) from M1/M2-like cells cultured in the presence of WSCPs/HA. Results. Results showed that WSCPs/HA formulations were able to significantly raise the wound closure rate, compared to the single constituents, promoting a complete wound closure after 18 h for WSCP1/HA (10 µg/mL) and after 24 h for WSCP2/HA (10 µg/mL), modulating the MMPs, TGFβ, and COX-2 gene expression. The effects of CM derived from M1/M2 polarized cells cultured in the presence of WSCPs/HA determined WH regulation, with a better ability of the WSCP2/HA formulation to modulate the time-dependent expression of reparative and inflammatory mediators. Conclusion. Our data underline the possible application of WSCPs/HA formulations as bioactive agents for the regulation of the wound repair process by the modulation of inflammatory and remodeling phases, affecting the activity of immune cells.

Amelioration of Full-Thickness Wound Using Hesperidin Loaded Dendrimer-Based Hydrogel Bandages

Wound healing is a complex biological phenomenon, having different but overlapping stages to obtained complete re-epithelization. The aim of the current study was to develop a dendrimer-based hydrogel bandage, to ameliorate full-thickness wounds. Hesperidin, a bioflavonoid found in vegetables and citrus fruits, is used for treatment of wounds; however, its therapeutic use is limited, due to poor water solubility and poor bioavailability. This issue was overcome by incorporating hesperidin in the inner core of a dendrimer. Hence, a dendrimer-based hydrogel bandage was prepared, and the wound healing activity was determined. A hemolysis study indicated that the hesperidin-loaded dendrimer was biocompatible and can be used for wound healing. The therapeutic efficacy of the prepared formulation was evaluated on a full-thickness wound, using an animal model. H&E staining of the control group showed degenerated neutrophils and eosinophils, while 10% of the formulation showed wound closure, formation of the epidermal layer, and remodeling. The MT staining of the 10% formulation showed better collagen synthesis compared to the control group. In vivo results showed that the preparation had better wound contraction activity compared to the control group; after 14 days, the control group had 79 ± 1.41, while the 10% of formulation had 98.9 ± 0.42. In a nutshell, Hsp-P-Hyd 10% showed the best overall performance in amelioration of full-thickness wounds.

Comparative palynological, physicochemical, antioxidant and antibacterial properties of Romanian honey varieties for biomedical applications

The aim of this study was to investigate the melissopalynology, physicochemical characteristics, antioxidant and antibacterial activity of seven honey samples harvested from different geographical regions and climates of Romania. The melissopalynological analysis revealed that monofloral and multifloral samples contained a wide diversity of minor pollen types from Romanian flora. The moisture, pH and free acidity values were within international limit. HPLC analysis indicated high content of fructose and glucose and low content of sucrose. Bioactive compounds including proteins, phenolics, flavonoids and ascorbic acid were present in variable quantities, according to the botanical origin and geographical area. The highest phenolics and ascorbic acid content was in multifloral honeys from Crisana mountain and meadow and the extrafloral honeydew honey. The same honey samples have exerted free radical scavenging and antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The free radical scavenging activity was strongly correlated to phenolics and ascorbic acid content, while the antimicrobial activity was medium correlated only to phenolics content. In conclusion, the selected Romanian honey samples with best antioxidant and antimicrobial activity could be further tested for the development of novel biomedical products.

Bee-Derived Products: Chemical Composition and Applications in Skin Tissue Engineering

Skin tissue regeneration is one of the population’s most common problems, and the complications that may appear in the healing process can have detrimental consequences. An alternative to conventional treatments could be represented by sustainable materials based on natural products, such as honey and its derivates (propolis, royal jelly, bee pollen, beeswax, and bee venom). They exhibit significant inhibitory activities against bacteria and have great potential in dermal tissue regeneration. Research in the pharmaceutical field demonstrates that conventional medication combined with bee products can deliver better results. The advantages include minimizing side effects and maintaining the same effectiveness by using low concentrations of antibiotic, anti-inflammatory, or chemotherapy drugs. Several studies suggested that bee products can replace the antimicrobial activity and efficiency of antibiotics, but further investigation is needed to establish a topical mixture’s potential, including honey, royal jelly, and propolis. Bee products seem to complete each other’s deficiencies, and their mixture may have a better impact on the wound healing process. The topic addressed in this paper highlights the usefulness of honey, propolis, royal jelly, bee pollen, beeswax, and bee venom in the re-epithelization process and against most common bacterial infections.

The Effect of Different Preoperative Depilation Ways on the Healing of Wounded Skin in Mice

Simple Summary

An increasing number of animals, including pets, may undergo surgery due to diseases or cesarean section nowadays. To reduce surgical site infection, hair removal is a necessary step before the surgical procedure because of the dense hair layer on the skin. However, previous studies showed that inappropriate hair removal methods might even increase surgical site infection rates. Although there are many commonly used preoperative depilation methods, it still has no detailed, unified selection criteria for animal preoperative hair removal. Therefore, we intend to provide a scientific and practical reference for veterinarians. To explore more specific details on whether depilation affects the condition of a surgical site, we established a skin wound model after the depilation step and then compared four commonly used hair-removal methods through morphological assessment and histopathological analysis. Ultimately, we concluded that the electric shaving method is the best method for preoperative depilation, followed by the depilatory cream method, and the sodium sulfide aqueous solution depilation method is the worst. We hope that the results of this study can provide useful reference points for veterinarians and researchers and help refine surgical procedures and maintain animal welfare.

Abstract

Hair removal is necessary before operating on animals with dense hair layers. To provide an appropriate hair removal method and maintain animal welfare, we introduced four commonly used depilation methods—namely, scissors shearing, electric shaving, depilatory cream, and sodium sulfide, and made systematic comparisons, instead of only examining one or two methods, as reported in the past. To further assess convenience and possible effects on skin wound healing, we performed a skin trauma model after depilation in C57BL/6J mice and recorded wound healing time. Meanwhile, the skin tissues around the wound were stained with H&E and Masson. The results showed that the wound contraction rate of the sodium sulfide group was significantly lower than other groups at different points in time. Furthermore, depilatory cream and sodium sulfide methods could induce a topical inflammatory response on the third day after the operation and delay the regeneration of collagen fibers. We concluded that sodium sulfide depilatory has a significant negative effect on wound healing. Depilatory cream is gentler, with mild skin irritation and symptoms of inflammation. The electric shaving method is more convenient and safer, and thus could be the best choice for preoperative depilation.

Machine learning models for prognosis prediction in endodontic microsurgery

OBJECTIVES

This study aimed to establish and validate machine learning models for prognosis prediction in endodontic microsurgery, avoiding treatment failure and supporting clinical decision-making.

METHODS

A total of 234 teeth from 178 patients were included in this study. We developed gradient boosting machine (GBM) and random forest (RF) models. For each model, 80% of the data were randomly selected for the training set and the remaining 20% were used as the test set. A stratified 5-fold cross-validation approach was used in model training and testing. Correlation analysis and importance ranking were conducted for feature selection. The predictive accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), F1 score, and the area under the curve (AUC) of receiver operating characteristic (ROC) curves were calculated to evaluate the predictive performance.

RESULTS

There were eight important predictors, including tooth type, lesion size, type of bone defect, root filling density, root filling length, apical extension of post, age, and sex. For the GBM model, the predictive accuracy was 0.80, with a sensitivity of 0.92, specificity of 0.71, PPV of 0.71, NPV of 0.92, F1 of 0.80/0.80, and AUC of 0.88. For the RF model, the accuracy was 0.80, with a sensitivity of 0.85, specificity of 0.76, PPV of 0.73, NPV of 0.87, F1 of 0.79/0.81, and AUC of 0.83.

CONCLUSIONS

The trained models were developed by eight common variables, showing the potential ability to predict the prognosis of endodontic microsurgery. The GBM model outperformed the RF model slightly on our dataset.

CLINICAL SIGNIFICANCE

Clinicians can use machine learning models for preoperative analysis in endodontic microsurgery. The models are expected to improve the efficiency of clinical decision-making and assist in clinician-patient communication.

A regenerative approach to the pharmacological management of hard-to-heal wounds

A wound is considered hard-to-heal when, despite the appropriate clinical analysis and intervention, the wound area reduces by less than a third at four weeks and complete healing fails to occur within 12 weeks. The most prevalent hard-to-heal wounds are associated with underlying metabolic diseases or vascular insufficiency and include arterial, venous, pressure and diabetic foot ulcers. Their common features include an abnormal immune response and extended inflammatory phase, a subdued proliferation phase due to cellular insufficiencies and finally an almost non-existent remodeling phase. Advances in wound care technology, tested in both pre-clinical models and clinical trials, have paved the way for improved treatment options, focused on regeneration. These interventions have been shown to limit the extent of ongoing inflammatory damage, decrease bacterial load, promote angiogenesis and deposition of granulation tissue, and stimulate keratinocyte migration thereby promoting re-epithelialization in these wounds. The current review discusses these hard-to-heal wounds in the context of their underlying pathology and potential of advanced treatment options, which if applied promptly as a standard of care, could reduce morbidity, promote quality of life, and alleviate the burden on a strained health system.

Collagen-Based Nanofibers for Skin Regeneration and Wound Dressing Applications

Skin regeneration after an injury is very vital, but this process can be impeded by several factors. Regenerative medicine is a developing biomedical field with the potential to decrease the need for an organ transplant. Wound management is challenging, particularly for chronic injuries, despite the availability of various types of wound dressing scaffolds in the market. Some of the wound dressings that are in clinical practice have various drawbacks such as poor antibacterial and antioxidant efficacy, poor mechanical properties, inability to absorb excess wound exudates, require frequent change of dressing and fails to offer a suitable moist environment to accelerate the wound healing process. Collagen is a biopolymer and a major constituent of the extracellular matrix (ECM), making it an interesting polymer for the development of wound dressings. Collagen-based nanofibers have demonstrated interesting properties that are advantageous both in the arena of skin regeneration and wound dressings, such as low antigenicity, good biocompatibility, hemostatic properties, capability to promote cellular proliferation and adhesion, and non-toxicity. Hence, this review will discuss the outcomes of collagen-based nanofibers reported from the series of preclinical trials of skin regeneration and wound healing.

An Overview of Cellulose Derivatives-Based Dressings for Wound-Healing Management

Presently, notwithstanding the progress regarding wound-healing management, the treatment of the majority of skin lesions still represents a serious challenge for biomedical and pharmaceutical industries. Thus, the attention of the researchers has turned to the development of novel materials based on cellulose derivatives. Cellulose derivatives are semi-synthetic biopolymers, which exhibit high solubility in water and represent an advantageous alternative to water-insoluble cellulose. These biopolymers possess excellent properties, such as biocompatibility, biodegradability, sustainability, non-toxicity, non-immunogenicity, thermo-gelling behavior, mechanical strength, abundance, low costs, antibacterial effect, and high hydrophilicity. They have an efficient ability to absorb and retain a large quantity of wound exudates in the interstitial sites of their networks and can maintain optimal local moisture. Cellulose derivatives also represent a proper scaffold to incorporate various bioactive agents with beneficial therapeutic effects on skin tissue restoration. Due to these suitable and versatile characteristics, cellulose derivatives are attractive and captivating materials for wound-healing applications. This review presents an extensive overview of recent research regarding promising cellulose derivatives-based materials for the development of multiple biomedical and pharmaceutical applications, such as wound dressings, drug delivery devices, and tissue engineering.

Wound Healing Effect of Gintonin Involves Lysophosphatidic Acid Receptor/Vascular Endothelial Growth Factor Signaling Pathway in Keratinocytes

Gintonin, a novel compound of ginseng, is a ligand of the lysophosphatidic acid (LPA) receptor. The in vitro and in vivo skin wound healing effects of gintonin remain unknown. Therefore, the objective of this study was to investigate the effects of gintonin on wound healing-linked responses, especially migration and proliferation, in skin keratinocytes HaCaT. In this study, 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay, Boyden chamber migration assay, scratch wound healing assay, and Western blot assay were performed. A tail wound mouse model was used for the in vivo test. Gintonin increased proliferation, migration, and scratch closure in HaCaT cells. It also increased the release of vascular endothelial growth factor (VEGF) in HaCaT cells. However, these increases, induced by gintonin, were markedly blocked by treatment with Ki16425, an LPA inhibitor, PD98059, an ERK inhibitor, 1,2-Bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid tetrakis (acetoxymethyl ester), a calcium chelator, and U73122, a PLC inhibitor. The VEGF receptor inhibitor axitinib also attenuated gintonin-enhanced HaCaT cell proliferation. Gintonin increased the phosphorylation of AKT and ERK1/2 in HaCaT cells. In addition, gintonin improved tail wound healing in mice. These results indicate that gintonin may promote wound healing through LPA receptor activation and/or VEGF release-mediated downstream signaling pathways. Thus, gintonin could be a beneficial substance to facilitate skin wound healing.