Tannic Acid Accelerates Cutaneous Wound Healing in Rats Via Activation of the ERK 1/2 Signaling Pathways

Tri-network PVA/chitosan/gelatin hydrogel modified by tannic acid with self-healing, adhesive and anti-inflammatory properties to accelerate wound healing

Wound inflammation is a key issue in wound healing as it often causes serious complications and delays wound healing. In this study, hemostatic and antimicrobial hydrogels composed of polyvinyl alcohol (PVA), chitosan (CS) and gelatin (Gel) were prepared. Phenylboronic acid (3-CPBA) and tannic acid (TA) were introduced to modify the multinetwork hydrogel to promote wound repair. PGCPT-1.2 hydrogel had a water content of >85 % and was biocompatible. Due to the antibacterial effect of chitosan itself. The PGCPT hydrogel exhibited 100 % antimicrobial activity against both Escherichia coli and Staphylococcus aureus within 12 h. The hydrogel exhibited shape memory behavior and self-healing ability. Histological analysis showed that PGCPT-1.2 hydrogel reduced tumor necrosis factor-α (TNF-α) levels by accelerating collagen deposition. The wound healing rate at day 14 was 97 % ± 0.4 %. PGCPT-1.2 hydrogel dressing with 1.2 % TA addition had the best effect in promoting wound healing, and it is a promising dressing for promoting wound healing and a therapeutic strategy worth developing.

Tannic Acid as an Ion Channel Modulator: An Understanding of Its Pharmacological Spectrum

Tannic acid (TA) is a polyphenol present in many plant foods and beverages such as green tea and wines. As a food additive, it has been recognized by Food and Drug Administration as generally safe. As a candidate drug, its pharmacological effects cover a wide spectrum, ranging from antibacterial, anticancer, cardioprotection to neuroprotection. TA has been shown to modulate a number of ion channels such as Ca2+-activated Cl- channels (CaCC), voltage-gated K+ (Kv) channels and transient receptor potential (TRP) channels, producing effects such as analgesia, antihypertensive effects and reduction of airway hypersensitivity. In this review we focus on how ion channel modulation by TA may account for the pharmacological effects of TA in various cells and organ systems. Further emphasis should be paid to factors, such as dosage and routes of administration, before the pharmacological actions of TA could be translated into therapeutic applications.

Comparison of Wound Healing Effects of Different Micro-Patterned Hydrogels on the Skin of Secondary Intention Rat Model

BACKGROUND

The skin acts as a barrier against external threats, and moisture is crucial for effective wound healing, as it promotes epithelial cell migration. Thus, a high water content supports wound healing by maintaining moisture, absorbing exudate, and forming a protective barrier. Here, we created three different micro-patterned hydrogels and tested them on rat skin wounds.

MATERIALS AND METHODS

Three different micro-patterned (waves, lines, and checks) hydrogel patches were created using three-dimensional polymer networks. On SD rat skin, wounds were created by making incisions, and the hydrogel patches were applied. The rats were divided into three experimental groups based on the hydrogel micro-patterns. Rats without hydrogel (vehicle) and those with flat hydrogel (no shape) were considered as controls. The wound closure rate (WCR) was calculated, and the expression of Col1A protein was measured by western blot.

RESULTS

After 7 days, the WCR was significantly higher in the groups treated with micro-patterned hydrogel patches compared to the vehicle and no-shape groups. Specifically, the WCR was highest in the checks micro-patterned hydrogel group compared to the waves and lines micro-patterned hydrogel groups. Furthermore, Col1A protein expression was evaluated at days 7 and 14, revealing a significant increase in expression after 14 days in the checks micro-patterned hydrogel group compared to the waves and lines micro-patterned hydrogel groups.

CONCLUSIONS

The checks micro-patterned hydrogel patches demonstrated superior wound healing efficacy, as indicated by a higher WCR and increased Col1A protein expression after 14 days. These findings highlight the importance of hydrogel pattern design in improving wound healing suggesting that optimized micro-patterns can enhance therapeutic outcomes in skin wound management.

Polyphenols in wound healing: unlocking prospects with clinical applications

Wound healing is a multifaceted, complex process that factors like aging, metabolic diseases, and infections may influence. The potentiality of polyphenols, natural compounds, has shown anti-inflammatory and antimicrobial properties in promoting wound healing and their potential applications in wound management. The studies reviewed indicate that polyphenols have multiple mechanisms that promote wound healing. This involves enhancing antioxidant defenses, reducing oxidative stress, modulating inflammatory responses, improving healing times, reducing infection rates, and enhancing tissue regeneration in clinical trials and in vivo and in vitro studies. Polyphenols have been proven to be effective in managing hard-to-heal wounds, especially in diabetic and elderly populations. Polyphenols have shown significant benefits in promoting angiogenesis and stimulating collagen synthesis. Polyphenol treatment has been demonstrated to have therapeutic effects in wound healing and chronic wound management. Their ability to regulate key healing processes makes them suitable for new wound care products and treatments. Future research should enhance formulations and delivery methods to optimize polyphenols' bioavailability and therapeutic efficacy in wound management approaches.

Microneedles as an Emerging Platform for Transdermal Delivery of Phytochemicals

Phytochemicals, which are predominantly found in plants, hold substantial medicinal value. Despite their potential, challenges such as poor oral bioavailability and instability in the gastrointestinal tract have limited their therapeutic use. Traditional intra/transdermal drug delivery systems offer some advantages over oral administration but still suffer from issues such as limited penetration depth, slow drug release rates, and inconsistent drug absorption. In contrast, microneedles (MNs) represent a significant advancement in intra/transdermal drug delivery by providing precise control over phytochemical delivery and enhanced penetration capabilities. By circumventing skin barriers, MNs directly access dermal layers rich in blood vessels and lymphatics, thus facilitating efficient phytochemical delivery. This review extensively discusses the obstacles of traditional oral delivery and the benefits of intra/transdermal delivery routes with a particular focus on the transformative potential of MNs for phytochemical delivery. This review explores the complexities of delivering phytochemicals through intra/transdermal routes, the development and types of MNs as innovative delivery tools, and the optimal design and properties of MNs for effective phytochemical delivery. Additionally, this review examines the versatile applications of MN-mediated phytochemical delivery, including its role in administering phytophotosensitizers for photodynamic therapy, and concludes with insights into relevant patents and future perspectives.

Broad-Spectrum Bactericidal Multifunctional Tiny Silicon-Based Nanoparticles Modified with Tannic Acid for Healing Infected Diabetic Wounds

Infected chronic wounds, in particular, diabetic wounds, are hard to heal, posing a global health concern with high morbidity and mortality rates. Diabetic full-thickness wounds infected with E. coli belong to the most difficult to heal chronic infected wounds. Here, we introduced tannic acid-modified silicon-based nanoparticles (TA-SiNPs) with broad-spectrum bactericidal activity that bacteria develop minimal resistance to, and they can effectively treat full-thickness wounds in diabetic mice infected with E. coli. Our findings indicate that these TA-SiNPs could achieve 100% antibacterial efficiency against S. aureus and 99.83% against E. coli, underlied by a positive surface charge and tannic acid groups facilitating bacterial membrane chemical composition depletion and depolarization of the membrane. In addition, we showed that spraying TA-SiNPs onto the skin wound of diabetic mice infected with E. coli resulted in wound healing with 98% closure after 12 days, in stark contrast to 49% of the control (PBS) and 68% of the one treated with Ofloxacin. Along with infection inhibition and ROS scavenging, we identified cell proliferation stimulation, inflammatory cytokine downregulation, and healing cytokine upregulation in the lesion, favoring the healing process. This study not only demonstrates the feasibility of employing silicon-based nanoparticles in diabetic wound healing for the first time, but also reports the first broad-spectrum bactericidal silicon nanodots. Furthermore, this provides novel insights into the mechanism of tannin-based nanoparticles disrupting bacterial membranes by depleting their chemical constituents. Our results highlighted that the developed TA-SiNPs are an effective nanomaterial for treating the infected chronic wounds.

Greener healing: sustainable nanotechnology for advanced wound care

Wound healing involves a carefully regulated sequence of events, encompassing pro-inflammatory and anti-inflammatory stages, tissue regeneration, and remodeling. However, in individuals with diabetes, this process gets disrupted due to dysregulation caused by elevated glucose levels and pro-inflammatory cytokines in the bloodstream. Consequently, the pro-inflammatory stage is prolonged, while the anti-inflammatory phase is delayed, leading to impaired tissue regeneration and remodeling with extended healing time. Furthermore, the increased glucose levels in open wounds create an environment conducive to microbial growth and tissue sepsis, which can escalate to the point of limb amputation. Managing diabetic wounds requires meticulous care and monitoring due to the lack of widely available preventative and therapeutic measures. Existing clinical interventions have limitations, such as slow recovery rates, high costs, and inefficient drug delivery methods. Therefore, exploring alternative avenues to develop effective wound-healing treatments is essential. Nature offers a vast array of resources in the form of secondary metabolites, notably polyphenols, known for their antimicrobial, anti-inflammatory, antioxidant, glucose-regulating, and cell growth-promoting properties. Additionally, nanoparticles synthesized through environmentally friendly methods hold promise for wound healing applications in diabetic and non-diabetic conditions. This review provides a comprehensive discussion and summary of the potential wound-healing abilities of specific natural polyphenols and their nanoparticles. It explores the mechanisms of action underlying their efficacy and presents effective formulations for promoting wound-healing activity.

Euphorbia hirta nanoextract as a piezoelectric ultrasonic scaler coolant in gingivitis treatment in a Wistar rat model

Objectives

This research was aimed at investigating the effects of various concentrations of Euphorbia hirta nanoextract as a piezoelectric scaler coolant on gingivitis healing in a Wistar rat model.

Methods

A piezoelectric ultrasonic scaler coolant was made from E. hirta nanoextract through ionic gelation. Experiments were conducted in 45 adult male Wistar rats divided into three groups treated with E. hirta nanoextract coolant (25%, 30%, and 35% concentrations), and negative and positive control groups. A silk ligature was used to trap debris and induce gingivitis in the maxillary incisors of the rats. Scaling was conducted with a piezoelectric ultrasonic scaler after the respective treatment for each group. Data were collected on days 3, 5, 7, 14, and 21 after treatment. Observations were collected with an Optilab® camera at 400× magnification. Angiogenesis and neutrophil data were analyzed with two-way analysis of variance (ANOVA) and post hoc Duncan tests at a 95% significance level.

Results

Use of E. hirta nanoextract as a piezoelectric ultrasonic coolant accelerated gingivitis healing in Wistar rats, particularly at a 25% concentration. Two-way ANOVA indicated a significant difference in angiogenesis and neutrophil counts between the control group and each treatment group (p < 0.05). Duncan's post-hoc test showed significant differences in mean neutrophil numbers and angiogenesis among groups on days 3, 5, 7, 14, and 21. The group treated with 25% nanoextract concentration showed no significant differences with respect to the positive control group.

Conclusions

Use of E. hirta nanoextract as a piezoelectric ultrasonic coolant had good therapeutic results in promoting gingivitis healing. E. hirta nanoextract may potentially resolve inflammation in gingivitis by modulating neutrophils and angiogenesis.

Network Pharmacology Study on Herb Pair Bletilla striata-Galla chinensis in the Treatment of Chronic Skin Ulcers

BACKGROUND

Herb pair Bletilla striata-Galla chinensis (BS-GC) is a classic combination of topical traditional Chinese medicine formulae in the treatment of chronic skin ulcers (CSUs).

OBJECTIVE

The aim of this study is to explore the effective active ingredients of BS-GC, as well as the core targets and signal transduction pathways of its action on CSUs.

METHODS

The ingredients of BS-GC were obtained from TCMSP and HERB databases. The targets of all active ingredients were retrieved from the SwissTargetPrediction database. The targets of CSUs were obtained from OMIM, GeneCards, Drugbank, and DisGeNET databases. A drug-disease target protein-protein interaction (PPI) network was constructed to select the most core targets, and an herb-ingredient-target network was built by utilizing Cytoscape 3.7.2. Furthermore, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes database (KEGG) analysis and verified the results of network pharmacology through molecular docking.

RESULTS

A total of 40 active ingredients from the herb pair BS-GC were initially screened, and a total of 528 targets were retrieved. Meanwhile, the total number of CSU targets was 1032. Then, the number of common targets between BS-GC and CSUs was 107. The 13 core targets of herb pair BS-GC with CSUs were filtered out according to the PPI network, including AKT1, TNF, EGFR, BCL2, HIF1A, MMP-9, etc. The 5 main core active ingredients were 1-(4-Hydroxybenzyl)-2-methoxy-9,10-dihydrophenanthrene-4,7-diol, 1-(4- Hydroxybenzyl)-4-methoxy-9,10-dihydrophenanthrene-2,7-diol, physcion, dihydromyricetin, and myricetin. The main biological processes were inflammation, oxidative stress, and immune response, involving the AGE-RAGE signaling pathway in diabetic complications, HIF-1 signaling pathway, NF-κB signaling pathway, and calcium signaling pathway. Molecular docking results showed good binding activity between the 5 main core active ingredients and 13 core targets.

CONCLUSION

This study predicted the core targets and signal transduction pathways in the treatment of CSUs to provide a reference for further molecular mechanism research.

Exosomal microRNAs from Mesenchymal Stem Cells: Novel Therapeutic Effect in Wound Healing

BACKGROUND

Wound healing is a complicated biological process that leads to the regeneration of damaged skin tissue. Determining the methods to promote wound healing has become a hot topic in medical cosmetology and tissue repair research. Mesenchymal stem cells (MSCs) are a group of stem cells with the potential of self-renewal and multi-differentiation. MSCs transplantation has a broad application prospect in wound healing therapy. Many studies have demonstrated that the therapeutic capacity of MSCs is mainly mediated by paracrine actions. Exosomes (EXOs), which are nanosized vesicles carrying a variety of nucleic acids, proteins and lipids, are an important component of paracrine secretion. It has been demonstrated that exosomal microRNAs (EXO-miRNAs) play a key role in the function of exosomes.

METHODS

In this review, we focus on current research on miRNAs from MSC-derived exosomes (MSC-EXO miRNAs) in terms of sorting, releasing and function and their effects on inflammation regulation, epidermal cell function, fibroblast function, and extracellular matrix formation. At last, we discuss the current attempts to improve the treatment of MSC-EXO-miRNAs.

RESULTS

Many studies have demonstrated that MSC-EXO miRNAs play a key role in promoting wound healing. They have been shown to regulate inflammation response, enhance epidermal cell proliferation and migration, stimulate fibroblast proliferation and collagen synthesis, and regulate extracellular matrix formation. Besides, there have been a number of strategies developed to promote MSC-EXO and MSC-EXO miRNAs for wound healing treatment.

CONCLUSION

Utilizing the association of exosomes from MSCs with miRNAs may be a promising strategy to promote trauma healing. MSC-EXO miRNAs may provide a new approach to promote wound healing and improve the quality of life for patients with skin injuries.

Exosomes from tannic acid-stimulated macrophages accelerate wound healing through miR-221-3p mediated fibroblasts migration by targeting CDKN1b

Tannic acid (TA) and its extraction were traditionally used for treatment of traumatic bleeding in China, and in the previous study we have demonstrated that TA could accelerate cutaneous wound healing in rats. We attempted to decipher the mechanism of TA in promoting wound healing. In this study, we found that TA could enhance the growth of macrophages and inhibit the release of inflammatory cytokines (IL-1β, IL-6, TNF-α, IL-8 and IL-10) through inhibition of NF-κB/JNK pathway. TA activated Erk1/2 pathway, leading to increased expressions of growth factors, bFGF and HGF. Scratch study revealed that TA did not directly regulate the migration function of fibroblasts, but could indirectly enhance fibroblasts migration by the supernatant of TA-treated macrophages. Transwell study further proved that TA stimulates macrophages to secrete exosomes enriched in miR-221-3p by activating the p53 signaling pathway, and the exosomes entered into the fibroblast cytoplasm and bound to 3'UTR of target gene CDKN1b which induced decreased expression level of CDKN1b, leading to promoting fibroblast migration. This study provided new insights into how TA accelerates wound healing in the inflammatory and proliferative phases of wound healing.

What’s old is new again: Insights into diabetic foot microbiome

Diabetes is a chronic disease that is considered one of the most stubborn global health problems that continues to defy the efforts of scientists and physicians. The prevalence of diabetes in the global population continues to grow to alarming levels year after year, causing an increase in the incidence of diabetes complications and health care costs all over the world. One major complication of diabetes is the high susceptibility to infections especially in the lower limbs due to the immunocompromised state of diabetic patients, which is considered a definitive factor in all cases. Diabetic foot infections continue to be one of the most common infections in diabetic patients that are associated with a high risk of serious complications such as bone infection, limb amputations, and life-threatening systemic infections. In this review, we discussed the circumstances associated with the high risk of infection in diabetic patients as well as some of the most commonly isolated pathogens from diabetic foot infections and the related virulence behavior. In addition, we shed light on the different treatment strategies that aim at eradicating the infection.

Bacterial cellulose membrane incorporated with silver nanoparticles for wound healing in animal model

The bacterial cellulose membrane (CM) is a promising biomaterial due to its easy applicability and moist environment. Moreover, nanoscale silver compounds (AgNO₃) are synthesized and incorporated into CMs to provide these biomaterials with antimicrobial activity for wound healing. This study aimed to evaluate the cell viability of CM incorporated with nanoscale silver compounds, determine the minimum inhibitory concentration (MIC) for Escherichia coli and Staphylococcus aureus, and its use on in vivo skin lesions. Wistar rats were divided according to treatment: untreated, CM (cellulose membrane), and AgCM (CM incorporated with silver nanoparticles). The euthanasia was performed on the 2nd, 7th, 14th, and 21st days to assess inflammation (myeloperoxidase-neutrophils, N-acetylglucosaminidase-macrophage, IL-1β, IL-10), oxidative stress (NO-nitric oxide, DCF-H₂O₂), oxidative damage (carbonyl: membrane's damage; sulfhydryl: membrane's integrity), antioxidants (superoxide dismutase; glutathione), angiogenesis, tissue formation (collagen, TGF-β1, smooth muscle α-actin, small decorin, and biglycan proteoglycans). The use of AgCM did not show toxicity, but antibacterial effect in vitro. Moreover, in vivo, AgCM provided balanced oxidative action, modulated the inflammatory profile due to the reduction of IL-1β level and increase in IL-10 level, in addition to increased angiogenesis and collagen formation. The results suggest the use of silver nanoparticles (AgCM) enhanced the CM properties by providing antibacterial properties, modulation the inflammatory phase, and consequently promotes the healing of skin lesions, which can be used clinically to treat injuries.

AuAg nanocomposites suppress biofilm-induced inflammation in human osteoblasts

Staphylococcus aureus (S. aureus)forms biofilm that causes periprosthetic joint infections and osteomyelitis (OM) which are the intractable health problems in clinics. The silver-containing nanoparticles (AgNPs) are antibacterial nanomaterials with less cytotoxicity than the classic Ag compounds. Likewise, gold nanoparticles (AuNPs) have also been demonstrated as excellent nanomaterials for medical applications. Previous studies have showed that both AgNPs and AuNPs have anti-microbial or anti-inflammatory properties. We have developed a novel green chemistry that could generate the AuAg nanocomposites, through the reduction of tannic acid (TNA). The bioactivity of the nanocomposites was investigated inS. aureusbiofilm-exposed human osteoblast cells (hFOB1.19). The current synthesis method is a simple, low-cost, eco-friendly, and green chemistry approach. Our results showed that the AuAg nanocomposites were biocompatible with low cell toxicity, and did not induce cell apoptosis nor necrosis in hFOB1.19 cells. Moreover, AuAg nanocomposites could effectively inhibited the accumulation of reactive oxygen species (ROS) in mitochondria and in rest of cellular compartments after exposing to bacterial biofilm (by reducing 0.78, 0.77-fold in the cell and mitochondria, respectively). AuAg nanocomposites also suppressed ROS-triggered inflammatory protein expression via MAPKs and Akt pathways. The current data suggest that AuAg nanocomposites have the potential to be a good therapeutic agent in treating inflammation in bacteria-infected bone diseases.

Bioinformatics-based and molecular docking study on the mechanism of action of Galla chinensis in the treatment of diabetic foot ulcers

Based on transcriptome sequencing and molecular biology, the active ingredient of Galla chinensis in the treatment of diabetic foot ulcers was identified, and its mechanism of action was analyzed.

Effects of dual-gene modification on biological characteristics of vascular endothelial cells and their significance as reserving cells for chronic wound repair

bFGF is a commonly used and reliable factor for improving chronic wound healing, and hSulf-1 expression is abundant in surrounding cells of chronic wound tissue and vascular endothelial cells, which can reverse the effect of bFGF and inhibit the signalling activity of cell proliferation. In this study, an adenovirus, Ad5F35ET1-bFGF-shSulf1, was designed for establishing the dual-gene modified vascular endothelial cells, which were used as the repair cells for skin chronic wound. Ad5F35ET1-bFGF-shSulf1 infected ECV304 cells in vitro and mediated the overexpression of bFGF and the knockdown of hSulf-1, which effectively activated the AKT and ERK signal transduction pathways, facilitate cell proliferation and migration, with the cell viability to 128.29% at 72 h after infection, compared to 66.65%, 73.74%, 87.63%, 103.14% in the blank control, Ad5F35ET1-EGFP-shNC, Ad5F35ET1-shSulf1, Ad5F35ET1-bFGF groups, respectively. In the rat ear skin injury model, the wound healing was significantly accelerated in the Ad5F35ET1-rbFGF-shrSulf1 group compared to the blank control group (p = 0.0046), Ad5F35ET1-EGFP-shNC group (p = 0.0245), Ad5F35ET1-shrSulf group (p = 0.0426), and Ad5F35ET1-rbFGF group (p = 0.2853). The results demonstrated that this strategy may be a candidate therapy for chronic injury repair.

RNA Sequencing Reveals the Regulation Mechanism of Yunnan Baiyao in Treating Skin Infection Caused by Staphylococcus aureus

Yunnan Baiyao is a well-known traditional Chinese medicine that can be formulated into a powder or capsule form. The mechanism by which it exerts its anti-inflammation effect, which is used in skin care products, needs to be further explored. In this study, we established the Staphylococcus aureus-induced mouse skin inflammatory model to investigate the effects of Yunnan Baiyao by the method of RNA-sequencing technology. The mice were randomly assigned to three groups, and those were control, model, and the Yunnan Baiyao-treated (YNtreated) group. Key genes and pathways were identified using bioinformatics analyses. In the study, we obtained 1,053 differentially expressed genes (DEGs) induced by Yunnan Baiyao. The 233 upregulated genes were enriched in 32 GO terms and 5 KEGG pathways, focused on the items, such as wound healing, cell metabolism, and proliferation, indicating the accelerating effects of Yunnan Baiyao on these aspects. The 820 downregulated genes were enriched mainly in the items, including the regulation of inflammation factor production, immune responses, and regulation of structure dermal components. Besides, Yunnan Baiyao reversed the expressions of 277 (201 decreased and 76 increased DEGs, respectively) induced by S. aureus. Ten key regulatory nodes (MMP2, PLK1, CCNB1, TLR4, CDK1, CCNA2, CDC25C, PDGFRA, MYOC, and KNG1) were identified by the construction of the protein interaction network, half of which were related to cell proliferation. VAV1 was another hub node that was affected by Yunnan Baiyao (Top 20). In the study, VAV1 and TLR4 can be considered key module genes in inflammation regulation. In conclusion, this study found that Yunnan Baiyao can significantly relieve inflammatory symptoms by regulating genes and pathways involved in the regulation of inflammation and immune response and also helped to deepen our understanding of the associated molecular mechanisms.

Pharmacological effects and mechanisms of tannic acid

In recent years, increasing attention has been paid to the pharmacological efficacy of tannins. Tannic acid (TA), the simplest hydrolysable tannin that has been approved by the FDA as a safe food additive, is one of the most important components of these traditional medicines. Studies have shown that TA displays a wide range of pharmacological activities, such as anti-inflammatory, neuroprotective, antitumor, cardioprotective, and anti-pathogenic effects. Here, we summarize the known pharmacological effects and associated mechanisms of TA. We focus on the effect and mechanism of TA in various animal models of inflammatory disease and organ, brain, and cardiovascular injury. Moreover, we discuss the possible molecular targets and signaling pathways of TA, in addition to the pharmacological effects of TA-based nanoparticles and TA in combination with chemotherapeutic drugs.

Mild Hyperthermia-Assisted ROS Scavenging Hydrogels Achieve Diabetic Wound Healing

Excessive reactive oxygen species (ROS) production induces oxidative damage to biomolecules, which can lead to the development of chronic diseases. Biocompatible hydrogel antioxidants composed of natural materials, such as polysaccharides and polyphenols, are of significant option for ROS scavenging. However, rapidly achieving hydrogel antioxidants with convenient, economical, safe, and efficient features remains challenging. Herein, facile synthesis of a physically cross-linked polyphenol/polysaccharide hydrogel by introducing tannic acid microsize particles (TAMP) into a cationic guar gum (CG) matrix is reported. Combining antioxidant/photothermal properties of TAMP and mechanical support from injectable CG, the formulated TAMP/CG is explored for treating diabetic wounds. Both in vitro and in vivo assays verify that TAMP/CG can protect the cells from ROS-induced oxidative damage, which can also be strengthened by the local photothermal heating (42 °C) triggered by near-infrared light. Overall, this study establishes the paradigm of enhanced diabetic wound healing by mild hyperthermia-assisted ROS scavenging hydrogels.

Alternative Approaches for the Management of Diabetic Foot Ulcers

Diabetic foot ulcers (DFU) represent a growing public health problem. The emergence of multidrug-resistant (MDR) bacteria is a complication due to the difficulties in distinguishing between infection and colonization in DFU. Another problem lies in biofilm formation on the skin surface of DFU. Biofilm is an important pathophysiology step in DFU and may contribute to healing delays. Both MDR bacteria and biofilm producing microorganism create hostile conditions to antibiotic action that lead to chronicity of the wound, followed by infection and, in the worst scenario, lower limb amputation. In this context, alternative approaches to antibiotics for the management of DFU would be very welcome. In this review, we discuss current knowledge on biofilm in DFU and we focus on some new alternative solutions for the management of these wounds, such as antibiofilm approaches that could prevent the establishment of microbial biofilms and wound chronicity. These innovative therapeutic strategies could replace or complement the classical strategy for the management of DFU to improve the healing process.

Assessing the mechanisms of action of natural molecules/extracts for phase-directed wound healing in hydrogel scaffolds

Hydrogels are proving to be very versatile as wound healing devices. In addition to their capabilities of providing a moist cellular environment and adaptive mechanical properties mimicking the extracellular matrix, they allow the incorporation of small molecules, which have potential impacts on cellular behaviour, in their nanostructures. This strategy can allow for specific targeting of the different stages of wound healing namely hemostasis, inflammation, and proliferative and remodelling phases. The latter include interlinked processes such as angiogenesis, collagen synthesis, growth factor release, collagen maturation and re-epithelialization. In this review, we attempt to match the mechanisms of action of natural molecules/extracts to the different stages of wound healing so that they can be used in a novel approach of multiphase-directed tissue regeneration using loaded hydrogel scaffolds.

Preparation and characterization of a novel polysialic acid/gelatin composite hydrogels cross-linked by tannic acid to improve wound healing after cesarean section dressing

The infections and delayed wound healing after cesarean delivery is one of the most complicated issues in surgical medicinal field. In the present investigation, designed novel polysialic acid loaded gelatin (PSA-Gel) composite hydrogels cross-linked by tannic acid (TA) has been developed and used as a facile wound dressing to improve cesarean wound healing ability with prevent bactericidal infections. The cross-linking effect was predominant when the TA content was lower, resulting in the formation of a cross-linked network. An effective TA cross-linking effect on the PSA-Gel hydrogel matrix was achieved when the amount of TA was around 15 wt %. The morphology of as-fabricated hydrogels was characterized using scanning electron microscopy (SEM) with an average pore sizes of PSA-Gel, PSA-Gel-TA-5%, PSA-Gel-TA-10%, and PSA-Gel-TA-15% hydrogels were 95.4 ± 12.6 μm, 120.4 ± 8.2 μm, 165.3 ± 21.6 μm, and 270.2 ± 32.5 μm, respectively. The effects of hydrogels on the swelling ratio, in vitro degradation, and mechanical properties were systemically evaluated. The TA cross-linked PSA-Gel hydrogels display strong antimicrobial behavior against gram-positive (Staphylococcus aureus) gram-negative (Escherichia coli) bacteria strains. Moreover, PSA-Gel-TA hydrogels also displayed favorable cytotoxicity toward L929 fibroblast cell lines. Finally, the therapeutic and wound healing potential of the PSA-Gel-TA hydrogels has been studied in vivo using the excision wound model in rats. The results indicate that the PSA-Gel-TA hydrogels have a greater and significant effect on wound closure and increased the wound healing rate compared with native PSA-Gel hydrogels and untreated control group at 94%, 73% and 65% on day 21. The findings suggest that PSA-Gel-TA hydrogels are promising dressing materials for the treatment of wound healing.

Anti-asthmatic effects of tannic acid from Chinese natural gall nuts in a mouse model of allergic asthma

Asthma is a chronic inflammatory disease of the airways, which is characterized by infiltration of inflammatory cells, airway hyperresponsiveness (AHR), and airway remodeling. This study aimed to explore the role and mechanism of tannic acid (TA), a naturally occurring plant-derived polyphenol, in murine asthma model. BALB/c mice were given ovalbumin (OVA) to establish an allergic asthma model. The results revealed that TA treatment significantly decreased OVA-induced AHR, inflammatory cells infiltration, and the expression of various inflammatory mediators (Th2 and Th1 cytokines, eotaxin, and total IgE). Additionally, TA treatment also attenuated increases in mucins (Muc5ac and Muc5b) expression, mucus production in airway goblet cells, mast cells infiltration, and airway remodeling induced by OVA exposure. Furthermore, OVA-induced NF-κB (nuclear factor- kappa B) activation and cell adhesion molecules expression in the lungs was suppressed by TA treatment. In conclusion, TA effectively attenuated AHR, inflammatory response, and airway remodeling in OVA-challenged asthmatic mice. Therefore, TA may be a potential therapeutic option against allergic asthma in clinical settings.

Polyherbal combination for wound healing: Matricaria chamomilla L. and Punica granatum L

BACKGROUND

Punica granatum L. (pomegranate) with astringent activities and Matricaria chamomilla L. (chamomile) with anti-inflammatory and antioxidant properties are natural remedies used for various skin disorders, including wound healing.

OBJECTIVES

This study was conducted to evaluate the individual and combined wound healing activity of the methanol extracts of pomegranate and chamomile flowers.

METHODS

After preparing the menthol fraction of pomegranate and chamomile flowers, the content of total phenols, total tannins, and total flavonoids of fractions was measured. For standardization of pomegranate and chamomile fractions, Gallic acid and apigenin-7-O-glucoside contents of them were determined using high-performance liquid chromatography (HPLC). Moreover, their antioxidant activities were examined using DPPH and FRAP tests. The antimicrobial assay was performed against Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Three different concentrations of methanol fraction of each plant and one combination dose of fractions were investigated for their wound healing activities in an excision wound model on the rats' dorsum. Finally, histopathological studies were done at the end of the experiment.

RESULTS

Phytochemical examinations showed high amounts of phenolic compounds in pomegranate flowers, while chamomile flower fractions contained a high amount of total flavonoids. Both fractions, especially pomegranate, had potent antioxidant activity. The best results for wound closure were observed 7 days after wound induction. All treated groups exhibited superior wound contraction compared to their placebo at all measurement times. The combined form of pomegranate and chamomile had better wound healing properties compared to a single therapy, especially on time earlier to wound induction.

CONCLUSION

This study represented high antioxidant and wound healing activities for methanol fraction of pomegranate and chamomile flowers, which could be related to their high content of phytochemicals. In comparison with single herb treatment, the combined form of these two fractions in lower concentrations accelerated wound closure.

Preparation and characterization of selenium-rich polysaccharide from Phellinus igniarius and its effects on wound healing

The modified of polysaccharides show various bio-activities. In our work, Phellinus igniarius Selenium-enriched mycelias polysaccharides (PSeP) were prepared from Phellinus igniarius, and its antioxidant and anti-inflammatory effects on injured mice were evaluated. The selenium content and physical properties of polysaccharides were characterized by GC, HPGPC, and FT-IR analysis. The results showed that PSeP could reduce reactive oxygen species (ROS) levels, myeloperoxidase (MPO) activity as well as malondialdehyde (MDA) content. Meanwhile, it increased the enzyme activities of glutathione peroxidase (GSH-Px) and catalase (CAT). Finally, it showed obvious wound healing effects in vivo. Moreover, PSeP could clear the ROS without obvious cytotoxicity. PSeP could further improve its ability to clear ROS level to promote skin wound healing in mice three days in advance.

Healing features of experimental injuries of soft tissues that contain foreign bodies in the form of fragments of military personnel uniforms

INTRODUCTION

The healing of combat wounds can be complicated by the presence of foreign bodies. The present research aimed to study the regeneration of soft tissue injuries complicated by foreign bodies in the form of fragments of military uniforms.

METHODS

60 rats were divided into four groups: intact (Int), control (Con) and two experimental (EG1, EG2). In Con, wounds were sutured without implantation of foreign bodies. A uniform consisting of 100% cotton was used as foreign bodies for EG1 and a uniform consisting of 65% cotton and 35% polyester for EG2. Histological studies were performed according to generally accepted methods. The growth factors wеre determined by ELISA.

RESULTS

In EG1, the inflammatory reaction proceeded protractedly, which complicated the development of granulation tissue. In EG2, considering the moderate inflammatory reactions, healing of the wounds became possible. The increase of the growth factors content in Con was maximal at the 15th day: basic fibroblast growth factor (bFGF)-2.2 times and vascular endothelial growth factor (VEGF)-1.6 times (p<0.001). In experimental groups, the bFGF content was maximal at the 60th day and exceeded the normal values by 1.7 times in EG1 and by 2.6 times in EG2 (p<0.001); the level of VEGF was slightly higher than that in healthy animals.

CONCLUSIONS

The study showed wound healing in all groups. The repair of injuries in rats of EG1 and EG2 was complicated by the textile implant and took longer. The dynamics of the content of growth factors reflected the impairment of wound healing processes. These violations were more pronounced in the EG1 group.

Polyphenols: A Promising Avenue in Therapeutic Solutions for Wound Care

In chronic wounds, the regeneration process is compromised, which brings complexity to the therapeutic approaches that need to be adopted, while representing an enormous loss in the patients’ quality of life with consequent economical costs. Chronic wounds are highly prone to infection, which can ultimately lead to septicemia and morbidity. Classic therapies are increasing antibiotic resistance, which is becoming a critical problem beyond complex wounds. Therefore, it is essential to study new antimicrobial polymeric systems and compounds that can be effective alternatives to reduce infection, even at lower concentrations. The biological potential of polyphenols allows them to be an efficient alternative to commercial antibiotics, responding to the need to find new options for chronic wound care. Nonetheless, phenolic compounds may have some drawbacks when targeting wound applications, such as low stability and consequent decreased biological performance at the wound site. To overcome these limitations, polymeric-based systems have been developed as carriers of polyphenols for wound healing, improving its stability, controlling the release kinetics, and therefore increasing the performance and effectiveness. This review aims to highlight possible smart and bio-based wound dressings, providing an overview of the biological potential of polyphenolic agents as natural antimicrobial agents and strategies to stabilize and deliver them in the treatment of complex wounds. Polymer-based particulate systems are highlighted here due to their impact as carriers to increase polyphenols bioavailability at the wound site in different types of formulations.

Role of Fibroblast Growth Factors Receptors (FGFRs) in Brain Tumors, Focus on Astrocytoma and Glioblastoma

Despite pharmacological treatments and surgical practice options, the mortality rate of astrocytomas and glioblastomas remains high, thus representing a medical emergency for which it is necessary to find new therapeutic strategies. Fibroblast growth factors (FGFs) act through their associated receptors (FGFRs), a family of tyrosine kinase receptors consisting of four members (FGFR1-4), regulators of tissue development and repair. In particular, FGFRs play an important role in cell proliferation, survival, and migration, as well as angiogenesis, thus their gene alteration is certainly related to the development of the most common diseases, including cancer. FGFRs are subjected to multiple somatic aberrations such as chromosomal amplification of FGFR1; mutations and multiple dysregulations of FGFR2; and mutations, translocations, and significant amplifications of FGFR3 and FGFR4 that correlate to oncogenesis process. Therefore, the in-depth study of these receptor systems could help to understand the etiology of both astrocytoma and glioblastoma so as to achieve notable advances in more effective target therapies. Furthermore, the discovery of FGFR inhibitors revealed how these biological compounds improve the neoplastic condition by demonstrating efficacy and safety. On this basis, this review focuses on the role and involvement of FGFRs in brain tumors such as astrocytoma and glioblastoma.

Polyphenol-Conjugated Bimetallic Au@AgNPs for Improved Wound Healing

Background

Polyphenols possess antioxidant, anti-inflammatory and antimicrobial properties and have been used in the treatment of skin wounds and burns. We previously showed that tannic acid-modified AgNPs sized >26 nm promote wound healing, while tannic acid-modified AgNPs sized 13 nm can elicit strong local inflammatory response. In this study, we tested bimetallic Au@AgNPs sized 30 nm modified with selected flavonoid and non-flavonoid compounds for wound healing applications.

Methods

Bimetallic Au@AgNPs were obtained by growing an Ag layer on AuNPs and further modified with selected polyphenols. After toxicity tests and in vitro scratch assay in HaCaT cells, modified lymph node assay as well as the mouse splint wound model were further used to access the wound healing potential of selected non-toxic modifications.

Results

Tannic acid, gallic acid, polydatin, resveratrol, catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate and procyanidin B2 used to modify Au@AgNPs exhibited good toxicological profiles in HaCaT cells. Au@AgNPs modified with 15 μM tannic acid, 200 μM resveratrol, 200 μM epicatechin gallate, 1000 μM gallic acid and 200 μM procyanidin B2 induced wound healing in vivo and did not lead to the local irritation or inflammation. Tannic acid-modified Au@AgNPs induced epithelial-to-mesenchymal transition (EMT) - like re-epithelialization, while other polyphenol modifications of Au@AgNPs acted through proliferation and wound closure.

Conclusion

Bimetallic Au@AgNPs can be used as a basis for modification with selected polyphenols for topical uses. In addition, we have demonstrated that particular polyphenols used to modify bimetallic nanoparticles may show different effects upon different stages of wound healing.

The Overexpression of Tβ4 in the Hair Follicle Tissue of Alpas Cashmere Goats Increases Cashmere Yield and Promotes Hair Follicle Development

Increased cashmere yield and improved quality are some goals of cashmere goat breeding. Thymosin beta-4 (Tβ4) plays a key role in the growth and development of hair follicles. For the past ten years, we have evaluated the role of Tβ4 by establishing a flock of 15 cashmere goats that specifically overexpress the Tβ4 gene in the hair follicles. These Tβ4 overexpression (Tβ4-OE) cashmere goats had more secondary hair follicles than the WT goats and produced more cashmere. Meanwhile, combined analysis of the skin transcriptome and proteome in cashmere goats suggested that Tβ4 may affect hair growth by interacting with keratin type II cytoskeletal 4 epidermal (KRT4) to mediate the extracellular signal-regulated protein kinase (ERK) signaling pathway, thereby promoting the development of secondary hair follicles, and consequently, increasing cashmere yield. Thus, the specific overexpression of Tβ4 in the hair follicles of cashmere goats effectively increased the cashmere yield.