Wound healing properties of flavonoids: A systematic review highlighting the mechanisms of action

Nanoemulsion containing Jatropha gossypiifolia leaf extract reduces dermonecrosis induced by Bothrops erythromelas venom and accelerates wound closure

ETHNOPHARMACOLOGICAL RELEVANCE

The species Jatropha gossypiifolia, popularly known as "pinhão-roxo", is distributed throughout Brazil, is commonly employed for topical or oral administration in treating wounds, inflammations, and snake bites. Given the significant impact of snakebites on public health and the limitations of antivenom, coupled with the diverse molecular composition of this plant species, investigating its healing and antidermonecrotic capacities is relevant.

AIM OF THE STUDY

This study aimed to develop a topical nanoemulsion incorporating the hydroethanolic extract of J. gossypiifolia leaves, to evaluate its therapeutic potential, particularly in terms of its efficacy in wound healing and inhibition of dermonecrosis induced by B. erythromelas venom (BeV).

MATERIAL AND METHODS

The extract of J. gossypiifolia (JgE) leaves was obtained by maceration and remaceration. The phytochemical analysis was conducted and J. gossypiifolia nanoemulsion (JgNe) was obtained, characterized and assessed for stability. The cytotoxicity was determined in normal cells (erythrocytes and 3T3) using hemolytic assay and cell viability assay using crystal violet staining. The antioxidant activity was evaluated by the reduction of ABTS and DPPH radicals. The evaluation of wound healing was conducted in vivo following treatment with JgNe, wherein the percentage of wound closure and inflammatory mediators. The skin irritation test was assessed in vivo by applying JgNe directly to the animal's skin. In vitro, the antivenom capacity was evaluated through enzymatic inhibition assays (phospholipase A2 and hyaluronidase) of BeV. Additionally, the in vivo antidermonecrotic activity of JgNe was evaluated by measuring the reduction of the dermonecrotic halo.

RESULTS

The HPLC-DAD analysis identified flavonoids, specifically vitexin, luteolin derivatives and apigenin derivatives. In addition, 95.08 ± 5.46 mg of gallic acid/g of extract and 137.92 ± 0.99 mg quercetin/g extract, was quantified. JgNe maintained stability over a 4-week period. Moreover, JgE and JgNe demonstrated no cytotoxicity in human erythrocytes and murine fibroblasts at tested concentrations (32.25-250 μg/mL). Additionally, exhibited significant antioxidant activity by reducing ABTS and DPPH radicals. The treatment with JgNe did not induce skin irritation and accelerated wound healing, with significant wound closure observed from 5th day and reduction in nitrite levels, myeloperoxidase activity, and cytokine. Both JgE and JgNe demonstrated in vitro inhibition of the phospholipase and hyaluronidase enzymes of BeV. Moreover, JgNe exhibited antidermonecrotic activity by reducing the dermonecrotic halo caused by BeV after 24 h.

CONCLUSIONS

JgNe and JgE exhibited no cytotoxicity at the tested concentrations. Additionally, our findings demonstrate that JgNe has the ability to accelerate wound closure and reduce dermonecrosis caused by BeV, indicating to be promising formulation for complementary therapy to antivenom treatment.

Flavonoid compounds and their synergistic effects: Promising approaches for the prevention and treatment of psoriasis with emphasis on keratinocytes - A systematic and mechanistic review

Psoriasis, a chronic autoimmune skin disorder, causes rapid and excessive skin cell growth due to immune system dysfunction. Numerous studies have shown that flavonoids have anti-psoriatic effects by modulating various molecular mechanisms involved in inflammation, cytokine production, keratinocyte proliferation, and more. This study reviewed experimental data reported in scientific literature and used network analysis to identify the potential biological roles of flavonoids' targets in treating psoriasis. 947 records from Web of Sciences, ScienceDirect database, Scopus, PubMed, and Cochrane library were reviewed without limitations until June 26, 2023. 66 articles were included in the systematic review. The ten genes with the highest scores, including interleukin (IL)-10, IL-12A, IL-1β, IL-6, Tumor necrosis factor-α (TNF-α), Janus kinase 2 (JAK 2), Jun N-terminal kinase (JUN), Proto-oncogene tyrosine-protein kinase Src (SRC), Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), and Signal transducer and activator of transcription 3 (STAT3), were identified as the hub genes. KEGG pathway analysis identified connections related to inflammation and autoimmune responses, which are key characteristics of psoriasis. IL-6, STAT3, and JUN's presence in both hub and enrichment genes suggests their important role in flavonoid's effect on psoriasis. This comprehensive study highlights how flavonoids can target biological processes in psoriasis, especially when combined for enhanced effectiveness.

A comprehensive review of the application of 3D-bioprinting in chronic wound management

INTRODUCTION

Chronic wounds require more sophisticated care than standard wound care because they are becoming more severe as a result of diseases like diabetes. By resolving shortcomings in existing methods, 3D-bioprinting offers a viable path toward personalized, mechanically strong, and cell-stimulating wound dressings.

AREAS COVERED

This review highlights the drawbacks of traditional approaches while navigating the difficulties of managing chronic wounds. The conversation revolves around employing natural biomaterials for customized dressings, with a particular emphasis on 3D-bioprinting. A thorough understanding of the uses of 3D-printed dressings in a range of chronic wound scenarios is provided by insights into recent research and patents.

EXPERT OPINION

The expert view recognizes wounds as a historical human ailment and emphasizes the growing difficulties and expenses related to wound treatment. The expert acknowledges that 3D printing is revolutionary, but also points out that it is still in its infancy and has the potential to enhance mass production rather than replace it. The review highlights the benefits of 3D printing for wound dressings by providing instances of smart materials that improve treatment results by stimulating angiogenesis, reducing pain, and targeting particular enzymes. The expert advises taking action to convert the technology's prospective advantages into real benefits for patients, even in the face of resistance to change in the healthcare industry. It is believed that the increasing evidence from in-vivo studies is promising and represents a positive change in the treatment of chronic wounds toward sophisticated 3D-printed dressings.

Natural Products with Potential Effects on Hemorrhoids: A Review

Hemorrhoid disease is a common anorectal disorder affecting populations worldwide, with high prevalence, treatment difficulties, and considerable treatment costs. Compared to other treatment options, medical therapy for hemorrhoids offers minimal harm, more dignity to patients, and is more economical. Unfortunately, there are few chemical hemorrhoid medications available clinically, which makes the search for efficacious, cost-effective, and environmentally friendly new medication classes a focal point of research. In this context, searching for available natural products to improve hemorrhoids exhibits tremendous potential. These products are derived from nature, predominantly from plants, with a minor portion coming from animals, fungi, and algae. They have excellent coagulation pathway regulation, anti-inflammatory, antibacterial, and tissue regeneration activities. Therefore, we take the view that they are a class of potential hemorrhoid drugs, prevention products, and medication add-on ingredients. This article first reviews the factors contributing to the development of hemorrhoids, types, primary symptoms, and the mechanisms of natural products for hemorrhoids. Building on this foundation, we screened natural products with potential hemorrhoid improvement activity, including polyphenols and flavonoids, terpenes, polysaccharides, and other types.

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

PURPOSE

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

METHODS

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

RESULT

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

CONCLUSION

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

From Ethnobotany to Biotechnology: Wound Healing and Anti-Inflammatory Properties of Sedum telephium L. In Vitro Cultures

Sedum telephium is a succulent plant used in traditional medicine, particularly in Italy, for its efficacy in treating localized inflammation such as burns, warts, and wounds. Fresh leaves or freshly obtained derivatives are directly applied to the injuries for these purposes. However, challenges such as the lack of microbiologically controlled materials and product standardization prompted the exploration of more controlled biotechnological alternatives, utilizing in vitro plant cell cultures of S. telephium. In the present study, we used HPLC-DAD analysis to reveal a characteristic flavonol profile in juices from in vivo leaves and in vitro materials mainly characterized by several kaempferol and quercetin derivatives. The leaf juice exhibited the highest content in total flavonol and kaempferol derivatives, whereas juice from callus grown in medium with hormones and callus suspensions showed elevated levels of quercetin derivatives. The in vitro anti-inflammatory and wound-healing assays evidenced the great potential of callus and suspension cultures in dampening inflammation and fostering wound closure, suggesting quercetin may have a pivotal role in biological activities.

Interaction of selected alkoxy naringenin oximes with model and bacterial membranes

Naringenin is a flavonoid found in many fruits and herbs, most notably in grapefruits. In recent years, this compound and its derivatives have been of great interest due to their high biological activity, including fungicidal and bactericidal effects, also in relation to multidrug-resistant bacteria. Membrane interactions of naringenin oxime (NO) and its 7-O-alkyl (7-alkoxy) derivatives, such as methyl (7MENO), ethyl (7ETNO), isopropyl (7IPNO), n-butyl (7BUNO) and n-pentyl (7PENO) were studied. Thermotropic properties of model membranes were investigated via differential scanning calorimetry (DSC), the influence on lipid raft mimicking giant unilamellar vesicles (GUVs) via fluorescence microscopy, and membrane permeability via measuring calcein leakage from liposomes. Molecular calculations supplemented the study. The influence of naringenin oximes on two strains of multidrug resistant bacteria: Staphylococcus aureus KJ and Enterococcus faecalis 37VRE was also investigated. In DSC studies all compounds reduced the temperature and enthalpy of main phase transition and caused disappearing of the pretransition. NO was the least active. The reduction in the area of surface domains in GUVs was observed for NO. Compounds NO and 7BUNO resulted in very low secretion of calcein from liposomes (permeability < 3 %). The highest results were observed for 7MENO (88.4 %) and 7IPNO (78.5 %). When bacterial membrane permeability was investigated all compounds caused significant release of propidium iodide from S. aureus (31.6-87.0 % for concentration 128 μg/mL). In the case of E. faecalis, 7ETNO (75.7 %) and NO (28.8 %) were the most active. The rest of the tested compounds showed less activity (permeability < 13.9 %). The strong evidence was observed that antibacterial activity of the tested compounds may be associated with their interaction with bacterial membrane.

Fabrication of Quercetin-Functionalized Morpholine and Pyridine Motifs-Laden Silk Fibroin Nanofibers for Effective Wound Healing in Preclinical Study

Choosing suitable wound dressings is crucial for effective wound healing. Spun scaffolds with bioactive molecule functionalization are gaining attention as a promising approach to expedite tissue repair and regeneration. Here, we present the synthesis of novel multifunctional quercetin with morpholine and pyridine functional motifs (QFM) embedded in silk fibroin (SF)-spun fibers (SF-QFM) for preclinical skin repair therapies. The verification of the novel QFM structural arrangement was characterized using ATR-FTIR, NMR, and ESI-MS spectroscopy analysis. Extensive characterization of the spun SF-QFM fibrous mats revealed their excellent antibacterial and antioxidant properties, biocompatibility, biodegradability, and remarkable mechanical and controlled drug release capabilities. SF-QFM mats were studied for drug release in pH 7.4 PBS over 72 h. The QFM-controlled release is mainly driven by diffusion and follows Fickian's law. Significant QFM release (40%) occurred within the first 6 h, with a total release of 79% at the end of 72 h, which is considered beneficial in effectively reducing bacterial load and helping expedite the healing process. Interestingly, the SF-QFM-spun mat demonstrated significantly improved NIH 3T3 cell proliferation and migration compared to the pure SF mat, as evidenced by the complete migration of NIH 3T3 cells within 24 h in the scratch assay. Furthermore, the in vivo outcome of SF-QFM was demonstrated by the regeneration of fresh fibroblasts and the realignment of collagen fibers deposition at 9 days post-operation in a preclinical rat full-thickness skin defect model. Our findings collectively indicate that the SF-QFM electrospun nanofiber scaffolds hold significant capability as a cost-effective and efficient bioactive spun architecture for use in wound healing applications.

Synthesis, characterization, and antibacterial effect of St. John's wort oil loaded chitosan hydrogel

Hydrogels prepared with natural and synthetic polymers were found to be applicable for the development of resistance against some Gram positive and negative bacterial species. Numerous studies have shown that chitosan polymers can be advantageous to be used in medicine due to their high antibacterial activity. In this study, biocompatible yellow cantorone oil doped hydrogels (chitosan/poly(vinyl alcohol) based) with antimicrobial properties were synthesized. The structural, morphological, swelling and mechanical properties of these biocompatible hydrogels prepared by double crosslinking were investigated and characterized. FTIR spectroscopy showed the appearance of new imine and acetal bonds due to both covalent cross-linking. In vitro cytotoxicity evaluation revealed that hydrogels showed weak cytotoxic effect. In the antimicrobial evaluation, it was determined that the hydrogel containing only chitosan showed better antimicrobial effect against Escherichia coli, Pseudomonas auriginosa, Staphylococcus aureus and Enterococcus faecalis bacteria than the one containing St. John's Wort oil. The antibacterial effect of polyvinyl alcohol/chitosan hydrogel was low. In our wound healing study, chitosan hydrogel loaded with yellow St. John's Wort oil was more effective in reducing wound size.

Photothermal-Controllable Microneedles with Antitumor, Antioxidant, Angiogenic, and Chondrogenic Activities to Sequential Eliminate Tracheal Neoplasm and Reconstruct Tracheal Cartilage

The optimal treatment for tracheal tumors necessitates sequential tumor elimination and tracheal cartilage reconstruction. This study introduces an innovative inorganic nanosheet, MnO2 /PDA@Cu, comprising manganese dioxide (MnO2 ) loaded with copper ions (Cu) through in situ polymerization using polydopamine (PDA) as an intermediary. Additionally, a specialized methacrylic anhydride modified decellularized cartilage matrix (MDC) hydrogel with chondrogenic effects is developed by modifying a decellularized cartilage matrix with methacrylic anhydride. The MnO2 /PDA@Cu nanosheet is encapsulated within MDC-derived microneedles, creating a photothermal-controllable MnO2 /PDA@Cu-MDC microneedle. Effectiveness evaluation involved deep insertion of the MnO2 /PDA@Cu-MDC microneedle into tracheal orthotopic tumor in a murine model. Under 808 nm near-infrared irradiation, facilitated by PDA, the microneedle exhibited rapid overheating, efficiently eliminating tumors. PDA's photothermal effects triggered controlled MnO2 and Cu release. The MnO2 nanosheet acted as a potent inorganic nanoenzyme, scavenging reactive oxygen species for an antioxidant effect, while Cu facilitated angiogenesis. This intervention enhanced blood supply at the tumor excision site, promoting stem cell enrichment and nutrient provision. The MDC hydrogel played a pivotal role in creating a chondrogenic niche, fostering stem cells to secrete cartilaginous matrix. In conclusion, the MnO2 /PDA@Cu-MDC microneedle is a versatile platform with photothermal control, sequentially combining antitumor, antioxidant, pro-angiogenic, and chondrogenic activities to orchestrate precise tracheal tumor eradication and cartilage regeneration.

Effect of Mexican Propolis on Wound Healing in a Murine Model of Diabetes Mellitus

Diabetes mellitus (DM) affects the wound healing process, resulting in impaired healing or aberrant scarring. DM increases reactive oxygen species (ROS) production, fibroblast senescence and angiogenesis abnormalities, causing exacerbated inflammation accompanied by low levels of TGF-β and an increase in Matrix metalloproteinases (MMPs). Propolis has been proposed as a healing alternative for diabetic patients because it has antimicrobial, anti-inflammatory, antioxidant and proliferative effects and important properties in the healing process. An ethanolic extract of Chihuahua propolis (ChEEP) was obtained and fractionated, and the fractions were subjected to High-Performance Liquid Chromatography with diode-array (HPLC-DAD), High-Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS) analyses and 46 compounds were detected. Deep wounds were made in a murine DM model induced by streptozotocin, and the speed of closure and the wound tensile strength were evaluated by the tensiometric method, which showed that ChEEP had similar activity to Recoveron, improving the speed of healing and increasing the wound tensile strength needed to open the wound again. A histological analysis of the wounds was performed using H&E staining, and when Matrix metalloproteinase 9 (MMP9) and α-actin were quantified by immunohistochemistry, ChEEP was shown to be associated with improved histological healing, as indicated by the reduced MMP9 and α-actin expression. In conclusion, topical ChEEP application enhances wound healing in diabetic mice.

Applications of propolis-based materials in wound healing

Due to its excellent antiseptic efficacy and antimicrobial properties, propolis has shown attractive advantages in wound dressings. However, an inclusive review of the propolis-based materials as a wound dressing is still lacking. The current short review summarizes the skin wound healing process, relates evaluation parameters, and then reviews the refined propolis-based materials dressings such as antimicrobial property, adhesion and hemostasis, anti-inflammatory and substance delivery. The approaches implemented to achieve these functions are classified and discussed. Furthermore, applications of propolis wound dressing for treating different types of wounds such as heal wounds, burns, and ulcers are presented. The future directions of propolis-based wound dressings for wound healing are further proposed. This review showed that propolis-based materials might be a promising new dressing for wound occlusion and tissue repairing.

Gongying-Jiedu-Xiji recipe promotes the healing of venous ulcers by inhibiting ferroptosis via the CoQ-FSP1 axis

Objective: Gongying-Jiedu-Xiji recipe (DDL, batch number Z01080175) reduces body temperature, detoxifies, activates the blood circulation, reduces swelling, and dispels decay and pus. The aim of this study was to investigate the mechanism of action by which DDL functions in the treatment of venous ulcers (VUs). Methods: Normal tissues as well as VU tissues before and after DDL treatment were collected from nine VU patients in the hospital with ethical approval. These three tissues were subjected to Prussian blue iron staining, immunoblotting, immunohistochemistry, immunofluorescence, and quantitative real-time PCR to detect the expression of ferroptosis suppressor protein 1 (FSP1), coenzyme Q (CoQ), 4-hydroxynonenal (4-HNE), and glutathione peroxidase 4 (GPX4). After successful validation of the heme-induced human foreskin fibroblast (HFF) ferroptosis model, lyophilized DDL powder was added to the cells, and the cells were subjected to viability assays, immunoblotting, flow cytometry, glutathione (GSH) and malonaldehyde (MDA) assays, electron microscopy and qPCR assays. Results: Ferroptosis in VU tissues was stronger than that in normal tissues, and ferroptosis in VU tissues after DDL treatment was weaker than that before treatment. Inhibition of CoQ and FSP1 and transfection of FSP1 influenced the effects of DDL. Conclusion: Our results suggest that DDL may promote healing by attenuating ferroptosis in VUs and that DDL may promote VU healing by modulating the CoQ-FSP1 axis.

Advanced application of nanotechnology in active constituents of Traditional Chinese Medicines

Traditional Chinese Medicines (TCMs) have been used for centuries for the treatment and management of various diseases. However, their effective delivery to targeted sites may be a major challenge due to their poor water solubility, low bioavailability, and potential toxicity. Nanocarriers, such as liposomes, polymeric nanoparticles, inorganic nanoparticles and organic/inorganic nanohybrids based on active constituents from TCMs have been extensively studied as a promising strategy to improve the delivery of active constituents from TCMs to achieve a higher therapeutic effect with fewer side effects compared to conventional formulations. This review summarizes the recent advances in nanocarrier-based delivery systems for various types of active constituents of TCMs, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones, from different natural sources. This review covers the design and preparation of nanocarriers, their characterization, and in vitro/vivo evaluations. Additionally, this review highlights the challenges and opportunities in the field and suggests future directions for research. Nanocarrier-based delivery systems have shown great potential in improving the therapeutic efficacy of TCMs, and this review may serve as a comprehensive resource to researchers in this field.

Lychnophora ericoides Mart. (Brazilian arnica) ethanol extract accelerates the skin wound healing process: Evidence for its mechanism of action

BACKGROUND

Lychnophora ericoides Mart, also known as the Brazilian arnica or fake arnica, belongs to the Asteraceae family. Leaves and roots are used in alcoholic and hydroalcoholic preparations for the treatment of wounds, inflammation, and pain.

PURPOSE

The present study aimed to investigate the effects of L. ericoides ethanolic extract (EELE) on cutaneous wound healing and the mechanisms of action involved.

METHODS

A total of 72 C57BL/6 mice were randomly divided into four groups of six animals each. An excisional wound was made in the dorsal region of each mouse. The test groups were topically treated with the vehicle, a positive control commercial reference drug, EELE ointment (5%), and EELE ointment (10%). The treatments were applied over 14 days. The wound area was measured every two days to verify the wound closure kinetics. On days 3, 7, and 14 the wound tissue samples were processed for Hematoxylin and Eosin, Masson-Trichrome, and Toluidine blue staining. The expression of renin-angiotensin system (RAS) components, the vascular growth factor-A (VEGF-A), the basic fibroblast growth factor (FGF-2), and type I collagen genes were evaluated. Phytochemical analyses were performed using HPLC-DAD and HPLC-MS/MS.

RESULTS

The EELE (10%) significantly reduced the wound area compared to the treatments used for the other groups. Histological analysis demonstrated that wounds treated with L. ericoides for 14 days developed improved anatomical skin features, healed with hair follicles and sebaceous glands, increased collagen production and angiogenesis, and decreased the number of mast cells at the injury site. Real-time PCR data demonstrated that groups treated with EELE (10%) showed increased Type I collagen, VEGF-A, FGF-2, and AT1R and decreased ACE II and receptor MAS. The healing action of L. ericoides may be related to the presence of phenolic compounds, such as phenolic acids, chlorogenic acid derivatives, and C-glycoside flavonoids.

CONCLUSION

Topical treatment with EELE increases important factors for wound healing: FGF, VEGF, collagen formation, and the expression of the proliferative axis of the renin-angiotensin system. For the first time, the present study shows the healing action of L. ericoides at the molecular level in an animal model. This process can be used as an alternative therapy for wound healing and the development of herbal therapy.

Accelerated wound healing induced by spinach extract in experimental model diabetic rats with streptozotocin

Patients with diabetes often have difficult-to-heal wounds. Spinacia oleracea extract comprises anti-inflammatory and anti-oxidative compounds; this research, therefore, studied the impact of Spinacia oleracea extracts on ulcer regeneration. This study was conducted on 72 adult Wistar rats (200 [Formula: see text] 20 g). They were randomly divided into six groups of twelve. A: Diabetic group receiving normal saline. B: Non-diabetic group receiving normal saline. C: Diabetic group receiving spinach aqueous extract. D: Diabetic group receiving spinach alcoholic extract. E: preventive group that received aqueous extract for 2 months. F: preventive group that received alcoholic extract for 2 months. Ulcer regeneration, vascular endothelium growth factor, blood sugar, and weight changes were measured on days 3, 7, 14, 21, and 30. Macroscopic investigation of the wounds non-diabetic control group, diabetic group, as well as spinach aqueous and alcoholic extract groups, were compared and there were significant changes (P < 0.05). Pathologic examination in the spinach aqueous and alcoholic extract groups, and nondiabetic group than in the diabetic group revealed significant advances (P <  0.05). On the third and seventh days, Vascular endothelium growth factor detected significant differences between groups (P < 0.05). Results indicate that, in regenerating diabetic ulcers, Spinacia oleracea may be effective. It influences the ulcer structure and speed.

Anti-Inflammatory and Histological Analysis of Skin Wound Healing through Topical Application of Mexican Propolis

Skin wound healing is a complex biochemical process of tissue repair and remodeling in response to injury. Currently, the drugs used to improve the healing process are inaccessible to the population, are costly, and have side effects, making the search for new treatment alternatives necessary. Propolis is a natural product produced by bees that is widely recognized and used in folk medicine for its multiple biomedical activities. However, therapeutic information regarding Mexican propolis is limited. This study aimed to evaluate the wound-healing effect of the Chihuahua ethanolic extract of propolis (ChEEP). Macroscopic and histological analyses were performed using a mouse wound-healing model. The topic acute toxicity assay showed that propolis at 10% w/v had no toxic effects. ChEEP has antibacterial activity against the Gram-positive bacteria Staphylococcus aureus and Staphylococcus epidermidis. Moreover, it exhibited good anti-inflammatory activity evaluated through mouse ear edema induced by 12-O-tetradeca-noylphorbol-13-acetate (TPA). A full-thickness incision lesion was created in mice and treated topically with 10% ChEEP. At Day 14 post-treatment, it was observed that propolis increased wound contraction and reduced healing time and wound length; furthermore, propolis increased the tensile strength of the wound, as determined with the tensiometric method, and promoted the formation of type I collagen at the site of injury, as evaluated with Herovici stain. These findings suggest that the topical administration of ChEEP can improve skin wound healing, probably due to the synergistic effect of its components, mainly polyphenols, in different steps of the wound-healing process. It should be noted this is the first time that the wound-healing activity of a Mexican propolis has been evaluated.

Antioxidant Activities of Natural Compounds from Caribbean Plants to Enhance Diabetic Wound Healing

Diabetic wound healing is a global medical challenge. Several studies showed that delayed healing in diabetic patients is multifactorial. Nevertheless, there is evidence that excessive production of ROS and impaired ROS detoxification in diabetes are the main cause of chronic wounds. Indeed, increased ROS promotes the expression and activity of metalloproteinase, resulting in a high proteolytic state in the wound with significant destruction of the extracellular matrix, which leads to a stop in the repair process. In addition, ROS accumulation increases NLRP3 inflammasome activation and macrophage hyperpolarization in the M1 pro-inflammatory phenotype. Oxidative stress increases the activation of NETosis. This leads to an elevated pro-inflammatory state in the wound and prevents the resolution of inflammation, an essential step for wound healing. The use of medicinal plants and natural compounds can improve diabetic wound healing by directly targeting oxidative stress and the transcription factor Nrf2 involved in the antioxidant response or the mechanisms impacted by the elevation of ROS such as NLRP3 inflammasome, the polarization of macrophages, and expression or activation of metalloproteinases. This study of the diabetic pro-healing activity of nine plants found in the Caribbean highlights, more particularly, the role of five polyphenolic compounds. At the end of this review, research perspectives are presented.

Couroupita guianensis bark decoction: From Amazonian medicine to the UHPLC-HRMS chemical profile and its role in inflammation processes and re-epithelialization

ETHNOPHARMACOLOGICAL RELEVANCE

In the Amazon rainforest, the shamans of the Mayantuyacu site use the healing virtues of decoctions and teas from different parts of the Couroupita guianensis Aubl. (Lecythidaceae) trees as remedies in Ashaninka medicine. However, composition of the remedy and the underlying mechanism remain unclear.

AIM OF THE STUDY

This study was designed to compare the metabolite profile of Couroupita guianensis bark decoction produced by Amazonian shamans with that obtained under standardised laboratory conditions and to investigate biological properties of both decoction and isolated constituents in skin wound healing process and inflammation.

MATERIALS AND METHODS

The chemical analyses were carried out by Ultra-High-Performance Liquid Chromatography coupled with UV and High-Resolution Mass Spectrometry detectors (UHPLC-UV-HRMS). 1D- and 2D-NMR experiments were performed to identify the main decoction constituents. The decoction and pure compound effect on keratinocyte migration was determined by the in vitro wound healing model; the mechanism of action was elucidated by western blot analysis.

RESULTS

UHPLC-UV-HRMS analysis revealed the occurrence of polyphenolic compounds as catechins, ellagitannins and, notably, of unusual sulphated derivatives of ellagic acid isolated for the first time from Couroupita guianensis bark. A new natural sulphated molecule [4-(2″-O-sulphate- β-D-glucuronopyranosyl) ellagic acid] was identified as the potential active compound responsible for the efficacy of bark decoction stimulating wound healing in human HaCaT keratinocytes. The molecular mechanism involved the induction of pro-migratory pathways mediated by ERK and AKT phosphorylation and the increase of MMP2 expression in HaCaT cells. At the same time, the treatment inhibited inflammation interfering with NFkB activation.

CONCLUSION

Beyond identifying a new bioactive compound, the overall results scientifically validate the traditional use of Couroupita guianensis bark decoction as an anti-inflammatory remedy. Moreover, the beneficial effects on keratinocytes suggest promising therapeutic applications in skin diseases.

Hyaluronic acid-quercetin pendant drug conjugate for wound healing applications

In this study, a simple approach was used for the synthesis of a water-soluble hyaluronic acid-quercetin (HA-Q) pendant drug conjugate to evaluate its potential wound-healing properties. The HA-Q conjugation was confirmed by Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible spectrophotometry (UV-Vis), and nuclear magnetic resonance (NMR) spectroscopy techniques. To produce the HA-Q, quercetin was conjugated on the HA backbone to the extent of 44.7 %. The HA-Q conjugate was soluble in water and a solution with a concentration of 20 mg/ml was prepared. The conjugate exhibited good biocompatibility and supported the growth and cell migration of skin fibroblast cells. HA-Q presented improved radical scavenging capacity compared to quercetin (Q) alone. The overall results confirmed the potential role of HA-Q in wound healing applications.

Flavonoids and their therapeutic applications in skin diseases

Flavonoids are a class of plant polyphenols found in a variety of fruits, vegetables, teas, and flowers. These compounds are present in many common dietary sources, such as green tea, wine, pomegranates, and turmeric, and possess a broad spectrum of biological activity due to their unique chemical structure. Flavonoids exhibit antioxidant, anti-inflammatory, antiviral, and anticarcinogenic properties that have been widely studied as potential therapeutics for diseases ranging from Alzheimer's disease to liver disease. There is currently significant research into therapeutic benefits of flavonoids in various skin conditions as these compounds have been shown to absorb ultraviolet radiation and modulate cancer and inflammation signaling pathways. This review discusses the current research in the application of flavonoids in skin diseases (e.g., prevention of premature photoaging, prevention and treatment of skin cancer, and promotion of skin wound healing) and their proposed mechanisms to provide a basis for future basic and translational research of flavonoids as potential drugs in the prevention and treatment of skin disorders.

Flavonoids and their therapeutic applications in skin diseases

Flavonoids are a class of plant polyphenols found in a variety of fruits, vegetables, teas, and flowers. These compounds are present in many common dietary sources, such as green tea, wine, pomegranates, and turmeric, and possess a broad spectrum of biological activity due to their unique chemical structure. Flavonoids exhibit antioxidant, anti-inflammatory, antiviral, and anticarcinogenic properties that have been widely studied as potential therapeutics for diseases ranging from Alzheimer's disease to liver disease. There is currently significant research into therapeutic benefits of flavonoids in various skin conditions as these compounds have been shown to absorb ultraviolet radiation and modulate cancer and inflammation signaling pathways. This review discusses the current research in the application of flavonoids in skin diseases (e.g., prevention of premature photoaging, prevention and treatment of skin cancer, and promotion of skin wound healing) and their proposed mechanisms to provide a basis for future basic and translational research of flavonoids as potential drugs in the prevention and treatment of skin disorders.

Horsetail (Equisetum hyemale) Extract Accelerates Wound Healing in Diabetic Rats by Modulating IL-10 and MCP-1 Release and Collagen Synthesis

Traditionally, Equisetum hyemale has been used for wound healing. However, its mechanism of action remains to be elucidated. For this purpose, a 40% ethanolic extract of E. hyemale was prepared. Phytochemical screening revealed the presence of minerals, sterols, phenolic acids, flavonols, a lignan, and a phenylpropenoid. The extract reduced the viability of RAW 264.7 cells and skin fibroblasts at all times evaluated. On the third day of treatment, this reduction was 30–40% and 15–40%, respectively. In contrast, the extract increased the proliferation of skin fibroblasts only after 48 h. In addition, the extract increased IL-10 release and inhibited MCP-1 release. However, the extract did not affect both TGF-β1 and TNF-α released by RAW 264.7 cells. The higher release of IL-10 could be related to the up-/downregulation of inflammatory pathways mediated by the extract components associated with their bioactivity. The extract inhibited the growth of Staphylococcus aureus and Escherichia coli. Topical application of the extract accelerated wound healing in diabetic rats by increasing fibroblast collagen synthesis. These results suggest that E. hyemale extract has great potential for use in the treatment of wounds thanks to its phytochemical composition that modulates cytokine secretion, collagen synthesis, and bacterial growth.

Wound healing activity and flavonoid contents of purslane (Portulaca grandiflora) of various varieties

Purslane has various varieties with different active metabolite contents that need to be explored further to find each variety's activity in wound healing. Different purslane herbs showed different antioxidant activities, suggesting they will have different flavonoid content and wound healing activity. This research aimed to evaluate purslane's total flavonoid content and wound-healing activity. The wounds induced on the rabbit back skin were divided into 6 treatment groups such as negative control, positive control, 10 and 20% purslane herbs extract varieties A, and 10 and 20% purslane herbs extract varieties C. Wounds were treated twice daily for 2 weeks, and measured on day 0, 7, 11, and 14. Total flavonoid content was measured with the AlCl3 colorimetric method. The wounds treated with 10 and 20% purslane herbs extract varieties A (Portulaca grandiflora magenta flower) have 0.32 ± 0.55 and 1.63 ± 1.96 mm wound diameters on day 7 and healed on day 11. The wounds treated with 10 and 20% purslane herbs extract varieties C (Portulaca grandiflora pink flower) showed 2.88 ± 0.51 and 0.84 ± 1.45 mm diameter and healed on day 11. The purslane herb A showed the highest wound healing activity, and purslane varieties A and C total flavonoid contents were 0.55 ± 0.02 and 1.58 ± 0.02% w/w, respectively.

Health functions and related molecular mechanisms of Miconia genus: A systematic review

The Miconia genus is traditionally used in folk medicine in Brazil and other tropical American countries and is represented by 282 species in this region. It is a multifaceted genus of medicinal plants widely used to treat rheumatoid arthritis (RA), pain, inflammatory diseases, and many more therapeutic applications. In the present study, we systematically identify and discuss the literature on in vivo and in vitro studies focusing on the therapeutic potentials and related molecular mechanisms of the Miconia genus. The review also assessed phytochemicals and their pharmacological properties and considered safety concerns related to the genus. Literature searches to identify studies on the Miconia genus were carried out through four main electronic databases, namely PubMed, Embase, Scopus, and Web of Science limited to Medical Subjects Headings (MeSH) and Descriptores en Ciencias de la Salud (DCS) (Health Sciences Descriptors) to identify studies published up to December 2022. The relevant information about the genus was gathered using the keywords 'Miconia', 'biological activities', 'therapeutic mechanisms', 'animal model, 'cell-line model', 'antinociceptive', 'hyperalgesia', 'anti-inflammatory', and 'inflammation'. The therapeutic potentials and mechanisms of action of 14 species from genus Miconia were examined in 18 in vitro studies and included their anti-inflammatory, anticancer, analgesic, antibacterial, cytotoxic, mutagenic, antioxidant, anti-leishmanial, antinociceptive, schistosomicidal, and anti-osteoarthritis potentials, and in eight in vivo studies, assessing their analgesic, antioxidant, antinociceptive, and anti-osteoarthritis activities. Some of the main related molecular mechanisms identified are the modulation of cytokines such as IL-1β, IL-6, and TNF-α, as well as the inhibition of inflammatory mediators and prostaglandin synthesis. The limited number of studies showed that commonly available species from the genus Miconia are safe for consumption. Miconia albicans Sw.Triana and Miconia rubiginosa (Bonpl.) DC was the most frequently used species and showed significant efficacy and potential for developing safe drugs to treat pain and inflammation.

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

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

The wound healing effect of botanicals and pure natural substances used in in vivo models

Repairing the wound is a multistep process that includes the spatial and temporal synchronization of a different range of cell types to increase the speed of wound contraction, the proliferation of epithelial cells, and collagen formation. The need for proper management of acute wounds to be cured and not turned into chronic wounds is a significant clinical challenge. The traditional practice of medicinal plants in many regions of the world has been used in wound healing since ancient times. Recent scientific research introduced evidence of the efficacy of medicinal plants, their phyto-components, and the mechanisms underlying their wound-repairing activity. This review aims to briefly highlight the wound-curing effect of different plant extracts and purely natural substances in excision, incision, and burn experimental animal models with or without infection of mice, rats (diabetic and nondiabetic), and rabbits in the last 5 years. The in vivo studies represented reliable evidence of how powerful natural products are in healing wounds properly. They have good scavenging activity against Reactive oxygen species (ROS) and anti-inflammatory and antimicrobial effects that help in the process of wound healing. It is evident that incorporating bioactive natural products into wound dressings of bio- or synthetic polymers in nanofiber, hydrogel, film, scaffold, and sponge forms showed promising results in different phases of the wound-curing process of haemostasis, inflammation, growth, re-epithelialization, and remodelling.

Wound healing properties of a new formulated flavonoid-rich fraction from Dodonaea viscosa Jacq. leaves extract

Background: Dodonaea viscosa Jacq. (D. viscosa) belongs to the family of Sapindaceae, commonly known as "Sinatha," and is used as a traditional medicine for treating wounds due to its high flavonoids content. However, to date there is no experimental evidence on its flavonoid-rich fraction of D. viscosa formulation as an agent for healing wounds. Objective: The present study aimed to evaluate the wound healing effect of ethyl acetate fraction of D. viscosa leaves on dermal wounds. Methods: The ethyl acetate fraction was produced from a water-ethanol extract of D. viscosa leaves and was quantitatively evaluated using the HPLC technique. The in-vivo wound healing ability of the ethyl acetate fraction of D. viscosa ointment (DVFO, 2.5%w/w and 5%w/w) was investigated in Sprague-Dawley rats utilizing an incision and excision paradigm with povidone-iodine ointment (5% w/w) as a control. The percentage of wound closure, hydroxyproline and hexosamine concentrations, tensile strength and epithelialization duration were measured. Subsequently, histopathology analysis of skin samples as well as western blots were performed for collagen type 3 (COL3A1), basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). Results: The ethyl acetate fraction of D. viscosa revealed flavonoids with high concentrations of quercetin (6.46% w/w) and kaempferol (0.132% w/w). Compared to the control group, the DVFO (2.5% and 5.0% w/w) significantly accelerated wound healing in both models, as demonstrated by quicker wound contraction, epithelialization, elevated hydroxyproline levels and increased tensile strength. Histopathological investigations also revealed that DVFO treatment improved wound healing by re-epithelialization, collagen formation and vascularization of damaged skin samples. Western blot analysis further demonstrated an up-regulation of COL3A, vascular endothelial growth factor and bFGF protein in wound granulation tissue of the DVFO-treated group (p < 0.01). Conclusion: It is concluded that flavonoid-rich D. viscosa ethyl acetate fraction promotes wound healing by up-regulating the expressions of COL3A, VEGF and bFGF protein in wound granulation tissue. However, extensive clinical and pre-clinical research on the flavonoid-rich fraction of D. viscosa is needed to determine its significant impact in the healing of human wounds.

Anadenanthera colubrina (Vell) Brenan: Ethnobotanical, phytochemical, pharmacological and toxicological aspects

ETHNOPHARMACOLOGICAL RELEVANCE

Anadenanthera colubrina (Vell.) Brenan is an endemic tree to South America and different parts of it are used by the population for the treatment of various diseases, as well as in indigenous rituals. This species has high pharmacological potential but may present toxic potential due to the presence of psychotropic compounds.

AIM OF THE STUDY

To review published studies with the species A. colubrina regarding ethnobotanical, phytochemical, pharmacological and toxicological aspects, as well as discuss perspectives for new research and protection of this species.

MATERIALS AND METHODS

A literature review was performed by accessing published articles on databases such as: PubMed, Science Direct, Scielo, Scopus, Taylor and Francis online, Springer Link, National Center for Biotechnology Information (NCBI), ACS Publications, Chemspider and Google Scholar. The keywords used were: "Anadenanthera colubrina" or "Mimosa colubrina" or "Piptadenia colubrina" or "Piptadenia macrocarpa" or "Piptadenia grata" or "Anadenanthera macrocarpa" and "medicinal plants" or "pharmacological" or "phytochemicals" or "traditional use" or "toxicological" or "ethnobotanical" or "pre-clinical trial" or "clinical". Articles found by database searches and search engines were screened at four stages: (i) title screening, (ii) locality screening, (iii) abstract screening, and (iv) full text. Other articles found through supplementary searches were screened in the full text whenever available. Each article was assessed by three reviewers at the title and abstract screening stages, except for those found in Portuguese databases that were assessed by the native reviewer.

RESULTS

This robust tree has been popularly useful for agroeconomic, medicinal and as a hallucinogen in religious rituals. According to the published studies, the main parts of the plant are the bark and seeds that are mostly used for respiratory conditions and as entheogens, respectively. It is a rich traditional herbal medicine with many pharmacological properties such as anti-inflammatory, antinociceptive, antidiarrheal, wound healing, antimicrobial, antitumoral, antioxidant, antiaddictive, insecticide and allelopathic that were described in in vitro and in vivo assays, and approximately 56 compounds were identified, suggesting a therapeutic potential for this species. Although most relate to medicinal uses, these are preliminaries and do not show the mechanism of action. The phytochemical assays showed the presence of phenolic compounds, flavonoids, triterpenes, steroids and alkaloids. Some of the compounds are anadanthoflavone, which is exclusive to this species, and no pharmacological or toxicological studies have yet demonstrated this compound. Another important compound is bufotenine which was isolated from seeds and is related to hallucinogenic and antiviral activity. The extracts made from leaves, bark, gum, and fruits appear to be safe, according to both in vivo and in vitro toxicology testing, which all shown low toxicity. Due to the presence of bufotenine in the seeds, it can be toxic, however, it was not found in toxicological assays with the seed extracts.

CONCLUSIONS

Therefore, part of the studies confirms the popular use of A. colubrina, however, more assays with isolated compounds and with the different extracts are necessary to corroborate other uses and the mechanism of action of their pharmacological effects needs to discuss in more detail. Therefore, the present review would be identified the gaps and suggests further studies oriented to validate the popular use. Thus, it must be noted that the use of this species must be controlled in order to minimize the environmental impact, as most of the pharmacological potential was shown with the bark and seeds. Due to its wide use in folk medicine, it is part of the Brazilian medicinal species with priority for conservation.

Antioxidative and Antimicrobial Evaluation of Bark Extracts from Common European Trees in Light of Dermal Applications

Plant species have developed effective defense strategies for colonizing diverse habitats and protecting themselves from numerous attacks from a wide range of organisms, including insects, vertebrates, fungi, and bacteria. The bark of trees in particular constitutes a number of components that protect against unwanted intruders. This review focuses on the antioxidative, dermal immunomodulatory, and antimicrobial properties of bark extracts from European common temperate trees in light of various skin pathogens, wound healing, and the maintenance of skin health. The sustainability aspect, achieved by utilizing the bark, which is considered a byproduct in the forest industry, is addressed, as are various extraction methods applied to retrieve extracts from bark.

Integrated network pharmacology and experimental validation to explore the mechanisms underlying naringenin treatment of chronic wounds

Naringenin is a citrus flavonoid with various biological functions and a potential therapeutic agent for skin diseases, such as UV radiation and atopic dermatitis. The present study investigates the therapeutic effect and pharmacological mechanism of naringenin on chronic wounds. Using network pharmacology, we identified 163 potential targets and 12 key targets of naringenin. Oxidative stress was confirmed to be the main biological process modulated by naringenin. The transcription factor p65 (RELA), alpha serine/threonine-protein kinase (AKT1), mitogen-activated protein kinase 1 (MAPK1) and mitogen-activated protein kinase 3 (MAPK3) were identified as common targets of multiple pathways involved in treating chronic wounds. Molecular docking verified that these four targets stably bound naringenin. Naringenin promoted wound healing in mice in vivo by inhibiting wound inflammation. Furthermore, in vitro experiments showed that a low naringenin concentration did not significantly affect normal skin cell viability and cell apoptosis; a high naringenin concentration was cytotoxic and reduced cell survival by promoting apoptosis. Meanwhile, comprehensive network pharmacology, molecular docking and in vivo and in vitro experiments revealed that naringenin could treat chronic wounds by alleviating oxidative stress and reducing the inflammatory response. The underlying mechanism of naringenin in chronic wound therapy involved modulating the RELA, AKT1 and MAPK1/3 signalling pathways to inhibit ROS production and inflammatory cytokine expression.

Cedrus deodara: In Vivo Investigation of Burn Wound Healing Properties

Objective

Cedrus deodara (Roxb. Ex Lamb.) G. Don possesses various biological activities, which have been documented in modern and traditional medicine. In this study, burn wound healing activity of the methanol extract of C. deodara wood was evaluated via a burn wound model in Wistar rats.

Methods

The methanol extract of C. deodara was evaluated for the contents of phenolic compounds, flavonoids, and tannins. Also, its antioxidant activity was determined using the DPPH assay. Then, a topical ointment containing the methanol extract of C. deodara (10%) was used to evaluate the healing effects on a model of second-degree thermal burn in 4 groups of 7 rats within 21 days. In this respect, average wound surface area, wound closure, and various histological features were examined.

Results

Our findings revealed that the wounds treated with the methanol extract of C. deodara showed higher wound contraction (33.6, 87.1, and 93.4% on days 7, 14, and 21, respectively) compared with the positive control (27.6, 80.7, and 88.3% on days 7, 14, and 21, respectively) and the negative control (20.1, 77.9, and 80.2% on days 7, 14, and 21, respectively). According to the results from epitheliogenesis score, the number of inflammatory cells, neovascularization, and collagen density, good burn wound healing activity of the methanol extract of C. deodarawas demonstrated.

Conclusion

Using the methanol extract of C. deodara in an ointment formulation can be developed to prevent or reduce burn injury progression.

Microbial Natural Products with Wound-Healing Properties

Wound healing continues to pose a challenge in clinical settings. Moreover, wound management must be performed properly and efficiently. Acute wound healing involves multiple cell divisions, a new extracellular matrix, and the process of formation, such as growth factors and cytokines, which are released at the site of the wound to regulate the process. Any changes that disrupt the healing process could cause tissue damage and prolong the healing process. Various factors, such as microbial infection, oxidation, and inflammation, can delay wound healing. In order to counter these problems, utilizing natural products with wound-healing effects has been reported to promote this process. Several natural products have been associated with wound healing, most of which are from medicinal plants. However, secondary microbial metabolites have not been extensively studied for their wound-healing properties. Further, investigations on the wound-healing control of natural microbial products are required due to a lack of studies. This review discussed the in vivo and in vitro research on the wound healing activities of natural microbial products, which may assist in the development of better wound treatments in the future.

Antileukemic, Antioxidant, Anti-Inflammatory and Healing Activities Induced by a Polyphenol-Enriched Fraction Extracted from Leaves of Myrtus communis L

Natural products have offered a number of exciting approaches in cancer treatment over the years. In this study, we investigated the prophylactic and therapeutic effects of the polyphenol-enriched fraction extracted from Myrtus communis (PEMC) on acute and chronic leukemia. According to the UHPLC-MSⁿ, the fraction is rich in flavonoids. Protective activity of the PEMC was assessed by evaluating the antioxidant, anti-inflammatory, wound healing, and hemolysis potential in a series of in vivo and in vitro assays, while the therapeutic approach consisted of the evaluation of cytotoxic activity of the PEMC against HL60 and K562 leukemia cell lines. Safety of the fraction was also evaluated on a non-cancerous Vero cell line and by an acute toxicity test performed in mice. The PEMC demonstrated a significant anti-inflammatory and healing potential. The activities found at the dose of 100 mg/kg were better than those observed using a reference drug. The PEMC demonstrated a significant antioxidant effect and a specific cytotoxicity towards HL60 (IC₅₀ = 19.87 µM) and K562 (IC₅₀ = 29.64 µM) cell lines being non-toxic to the Vero cell line. No hemolytic activity was observed in vitro and no toxicity effect was found in mice. Thus, the PEMC has a pharmacological potential as both preventive and therapeutic agent. However, further research is necessary to propose its mechanism of action.

Evaluation of In Vivo Wound-Healing and Anti-Inflammatory Activities of Solvent Fractions of Fruits of Argemone mexicana L. (Papaveraceae)

INTRODUCTION

The solvent fractions of the fruits of Argemone mexicana L. (Papaveraceae) have not yet been explored scientifically for in vivo wound healing and anti-inflammatory activities. The objective of this study was, therefore, to evaluate in vivo wound healing and anti-inflammatory activities of the solvent fractions of the fruit of Argemone mexicana L. (Papaveraceae) in rats.

METHOD

The crude extract of Argemone mexicana was fractionated with n-hexane, ethyl acetate, and distilled water. Wound healing activity was evaluated using excision and incision wound models while anti-inflammatory activity was evaluated using carrageenan-induced rat paw and cotton pellet-induced granuloma models. The fractions were evaluated at 5 and 10% ointments using moist-exposed burn ointment as the standard drug, and 100, 200, and 400 mg/kg test doses using aspirin, and dexamethasone as standard drugs for wound healing and anti-inflammatory activities, respectively. All treatment administrations were made orally for anti-inflammatory activity and applied topically for wound healing activity.

RESULT

The 10% w/w ethyl acetate fraction ointment showed a significant percentage of wound contraction, reduced period of epithelialization, increased amount of fibrosis, neovascularization, and collagen tissue formation (p < 0.01). The ethyl acetate fraction also showed a significant increase in tensile strength (55%; p < 0.01) and (81.10%; p < 0.01) at the tested doses of 5 and 10% w/w ointments, which was comparable to moist-exposed burn ointment. The ethyl acetate fraction also revealed a significant percent edema inhibition (61.41%; p < 0.01), suppression of the exudate (38.09% p < 0.01), and granuloma mass formations (53.47% p < 0.01) at the tested dose of 400 mg/kg.

CONCLUSION

The results of this study showed that the Ethyl acetate fraction of Argemone mexicana fruit has significant wound healing and anti-inflammatory activities which support the traditional claims of the experimental plant.

Wound Healing versus Metastasis: Role of Oxidative Stress

Many signaling pathways, molecular and cellular actors which are critical for wound healing have been implicated in cancer metastasis. These two conditions are a complex succession of cellular biological events and accurate regulation of these events is essential. Apart from inflammation, macrophages-released ROS arise as major regulators of these processes. But, whatever the pathology concerned, oxidative stress is a complicated phenomenon to control and requires a finely tuned balance over the different stages and responding cells. This review provides an overview of the pivotal role of oxidative stress in both wound healing and metastasis, encompassing the contribution of macrophages. Indeed, macrophages are major ROS producers but also appear as their targets since ROS interfere with their differentiation and function. Elucidating ROS functions in wound healing and metastatic spread may allow the development of innovative therapeutic strategies involving redox modulators.

The Potential Therapeutic Properties of Prunetin against Human Health Complications: A Review of Medicinal Importance and Pharmacological Activities

BACKGROUND

Flavonoids are polyphenolic compounds found to be present in nature and abundant in flowers and fruits. Flavonoidal class phytochemicals have gained interest in the scientific field because of their important pharmacological activities. Several scientific studies have revealed anti-bacterial, anti-oxidant, anti-fungal, analgesic, anti-viral, anti-inflammatory, anti-tumor, anti-parasitic and anti-allergic activities of flavonoidal class phytochemicals. Prunetin is an O-methylated isoflavone that belongs to the phytochemical phytoestrogen class, found to be present in licorice, red cherry, soybean and legumes.

METHODS

Biological potential and pharmacological activities of prunetin have been investigated in the present work through scientific data analysis of numerous scientific research works. Numerous literature databases have been searched in order to collect the scientific information on prunetin in the present work. Pharmacological activities of prunetin have been investigated in the present work through literature data analysis of different scientific research works. Scientific data have been collected from Google Scholar, Google, PubMed, Science Direct and Scopus. Analytical data on prunetin has been collected from literature sources and analyzed in the present work.

RESULTS

Scientific data analysis revealed the biological importance of prunetin in medicine. Prunetin was found to be present in the pea, peach, Oregon cherry, skimmed cheese, cheese, cow kefir and goat kefir. Prunetin is also present in the Prunus avium, Andira surinamensis, Butea superba, Dalbergia sympathetica, Ficus nervosa, Pterospartum tridentatum and Pycnanthus angolensis. Pharmacological data analysis revealed the biological importance of prunetin on bone disorders, cancers, especially hepatocellular carcinoma, urinary bladder cancer, gastric cancer, ovarian cancer, human airway, gut health and enzymes. Scientific data analysis revealed biological effectiveness of prunetin for their angiogenic effects, anti-inflammatory, anti-oxidant, antimicrobial, estrogenic and vasorelaxant potential. Analytical data revealed the importance of modern analytical techniques for qualitative and quantitative analysis of prunetin in the scientific fields.

CONCLUSION

Scientific data analysis in the present investigation revealed the biological importance and pharmacological activities of prunetin in medicine.

Attenuation of dermal wounds through topical application of ointment containing phenol enriched fraction of Caesalpinia mimosoides Lam

Caesalpinia mimosoides Lam. is one of the important medicinal plants used by the traditional healers of Uttara Kannada district, Karnataka (India) for treating wounds. In our previous study ethanol extract of the plant was evaluated for its wound healing activity. In continuation, the present study was aimed to evaluate the phenol enriched fraction (PEF) of ethanol extract for wound healing activity along with its antioxidant, anti-inflammatory and antimicrobial properties. The potent wound healing activity of PEF was evidenced by observation of increased rate of cell migration in L929, 3T3L1 and L6 cells (92.59 ± 1.53%, 98.42 ± 0.82% and 96.63 ± 0.61% respectively) at 7.81 μg/ml doses in assays carried out in vitro. Significantly enhanced rate of wound contraction (97.92 ± 0.41%), tensile strength (973.67 ± 4.43 g/mm2), hydroxyproline (31.31 ± 0.64 mg/g) and hexosamine (8.30 ± 0.47 mg/g) contents were observed on 15th post wounding day in 5% PEF treated animals. The enzymatic and non-enzymatic cellular antioxidants (superoxide dismutase, catalase and reduced glutathione) were upregulated (15.89 ± 0.17 U/mg, 48.30 ± 4.60 U/mg and 4.04 ± 0.12 μg/g respectively) with the administration of 5% PEF. The significant antimicrobial, antioxidant and anti-inflammatory activities support the positive correlation of PEF with its enhanced wound healing activity. PEF contains expressive amounts of total phenolic and total flavonoid contents (578.28 ± 2.30 mg GAE/g and 270.76 ± 2.52 mg QE/g). Of the various chemicals displayed in RP-UFLC-DAD analysis of PEF, gallic acid (68.08 μg/mg) and ethyl gallate (255.91 μg/mg) were predominant. The results indicate that PEF has great potential for the topical management of open wounds.

Evolving spectrum of diabetic wound: Mechanistic insights and therapeutic targets

Diabetes mellitus is a chronic metabolic disorder resulting in an increased blood glucose level and prolonged hyperglycemia, causes long term health conse-quences. Chronic wound is frequently occurring in diabetes patients due to compromised wound healing capability. Management of wounds in diabetic patients remains a clinical challenge despite many advancements in the field of science and technology. Increasing evidence indicates that alteration of the biochemical milieu resulting from alteration in inflammatory cytokines and matrix metalloproteinase, decrease in fibroblast and keratinocyte functioning, neuropathy, altered leukocyte functioning, infection, etc., plays a significant role in impaired wound healing in diabetic people. Apart from the current pharmacotherapy, different other approaches like the use of conventional drugs, antidiabetic medication, antibiotics, debridement, offloading, platelet-rich plasma, growth factor, oxygen therapy, negative pressure wound therapy, low-level laser, extracorporeal shock wave bioengineered substitute can be considered in the management of diabetic wounds. Drugs/therapeutic strategy that induce angiogenesis and collagen synthesis, inhibition of MMPs, reduction of oxidative stress, controlling hyperglycemia, increase growth factors, regulate inflammatory cytokines, cause NO induction, induce fibroblast and keratinocyte proliferation, control microbial infections are considered important in controlling diabetic wound. Further, medicinal plants and/or phytoconstituents also offer a viable alternative in the treatment of diabetic wound. The focus of the present review is to highlight the molecular and cellular mechanisms, and discuss the drug targets and treatment strategies involved in the diabetic wound.

Evaluation of the healing properties of Garcinia brasiliensis extracts in a cutaneous wound model

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing is a complex process that can leave pathological scars, especially in case of infections from opportunistic microorganisms. In this context, herbal medicines open up great possibilities for investigation. One of the species of interest native to Brazil is Garcinia brasiliensis ("bacupari"). Traditionally known for treating wounds and ulcers, G. brasiliensis presents anti-inflammatory, antioxidant and antimicrobials properties. But, its wound healing profile in experimental models, in order to validate its efficacy, is still litle studied.

AIM OF THE STUDY

Thus, the objective of this work was to evaluate, in an infected cutanous wound model, the potential of formulations incorporated with G. brasiliensis leaves extracts.

MATERIALS AND METHODS

Crude extract (CE), Ethyl Acetate Fraction (EAF) and Hexanic Fraction (HF) were submitted to phytochemical assays, high performance thin layer chromatography (HTPLC) and cytotoxicity studies. CE and EAF were also tested for microbicidal properties and incorporated in cream and gel formulations at 10% concentration. After stability testing, the gel formulations with CE or EAF at 10% were selected and applied to skin wounds infected or not with Staphylococcus aureus in Wistar rats. The healing potenttial of the extracts was verified by the expression of the protein Annexin A1 (AnxA1), related to the processes of inflammation and antifibrotic function, the cells immunostaining for Gasdermin-D (GSDM-D), a marker of pyroptotic cell death, and the dosage of interleukin-10 (IL-10) and monocyte chemotactic protein (MCP)-1 inflammatory mediators.

RESULTS

Phytochemical studies indicated the presence of compounds of pharmacological interest, including Catechin, Quercetin and Berberine in addition to low cytotoxicity of CE and EAF at 10%. After the 6-day topical treatments, CE and EAF gel formulations demonstrated to control the pruritus formation process. The treatments decreased AnxA1 expression and the amount of cells immunostained for GSDM-D, and increased the expression of MCP-1 in infected wounds.

CONCLUSIONS

Together, the results show important anti-inflammatory profile and skin healing potential of CE and EAF from G. brasiliensis leaves, even in infected lesions, with therapeutic perspectives.

Nanostructured Electrospun Polycaprolactone-Propolis Mats Composed of Different Morphologies for Potential Use in Wound Healing

This study aimed to investigate different types of morphologies obtained using the electrospinning process to produce a material that enables wound healing while performing a controlled release. Using benign solvents, the authors prepared and characterised electrospun polycaprolactone mats loaded with propolis, a popular extract in traditional medicine with potential for skin repair. Different morphologies were obtained from distinct storage periods of the solution before electrospinning to investigate the effect of PCL hydrolysis (average diameters of fibres and beads: 159.2-280.5 nm and 1.9-5.6 μm, respectively). Phytochemical and FTIR analyses of the extract confirmed propolis composition. GPC and viscosity analyses showed a decrease in polymer molecular weight over the storage period (about a 70% reduction over 14 days) and confirmed that it was responsible for the nanostructure diversity. Moreover, propolis acted as a lubricant agent, affecting the spun solutions' viscosity and the thermal properties and hydrophilicity of the mats. All samples were within the value range of the water vapour transpiration rate of the commercial products (1263.08 to 2179.84 g/m²·day). Even though the presence of beads did not affect the propolis release pattern, an in vitro wound-healing assay showed that propolis-loaded mats composed of beaded fibres increased the cell migration process. Thus, these films could present the potential for use in wound dressing applications.

Prenylated Flavonoids in Topical Infections and Wound Healing

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

Validation of the traditional medicinal use of a Mexican endemic orchid (Prosthechea karwinskii) through UPLC-ESI-qTOF-MS/MS characterization of its bioactive compounds

Ethnopharmacological relevance

The orchid Prosthechea karwinskii is a medicinal orchid in Oaxaca, Mexico, used to treat diabetes, cough, wounds, and burns, prevent miscarriage and assist in labor. Each part of the plant (leaves, pseudobulbs, or flowers) is used by healers for certain treatment conditions, indicating that each part has different biocompounds with specific pharmacological activity.

Aim of the study

To characterize the biocompounds in extracts from leaves, pseudobulbs, and flowers of P. karwinskii and evaluate their ROS inhibition capacity to associate it with medicinal uses.

Materials and methods

The compounds present in extracts from leaves, pseudobulbs, and flowers of P. karwinskii were identified by UPLC-ESI-qTOF-MS/MS. The chemical differentiation of each extract was tested by principal component analysis (PCA) using compound intensity values. For each extract, total phenol and flavonoid contents were quantified. Their antioxidant capacity was evaluated ex vivo by inhibition of ROS with DCFH-DA and in vitro with DPPH radical.

Results

Based on the PCA, it was observed that some compounds were completely separated from others according to the correlation that they presented. The compounds common to all three plant parts were quinic, malic, succinic, azelaic, and pinellic acids. Among the compounds identified, two were exclusive to leaves, four to pseudobulbs, and ten to flowers. Some of the identified compounds have well-known antioxidant activity. The leaves had the highest content of total phenols and flavonoids, and the highest in vitro and ex vivo antioxidant capacity. A strong correlation was observed between phenol and flavonoid contents, and antioxidant capacity ex vivo and in vitro.

Conclusions

It was found that the bioactive compounds and antioxidant capacity of each part of the plant were associated with its traditional medicinal use. A pharmacological potential was also found in P. karwinskii for further biological studies because of the type of compounds it contained.

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Compounds common and specific to each plant part were identified by UPLC-ESI-qTOF-MS/MS.

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The biological activities reported for the identified compounds validate the traditional medicinal use of P. karwinskii.

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Embelin (inflammation) is exclusive to leaves, phloridzin (diabetes) to pseudobulbs, and abscisic acid (in labor) to flowers.

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In the literature, the antioxidant compounds are rutin, kaempferol-3-O-rutinoside, embelin, guanosine, and azelaic acid.

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Pearson's correlation coefficients indicate that a higher content of phenols and flavonoids has a higher antioxidant capacity.

Wound Healing Properties of Jasione montana Extracts and Their Main Secondary Metabolites

The effects of different extracts obtained from Jasione montana L. (JM1-JM6) and their main metabolites on biological processes during wound healing were evaluated. The effect on wound closure in the scratch test was established, and collagen type I synthesis and anti-inflammatory effects were assessed by flow cytometry in a human dermal fibroblast model (PCS-201-012). Additionally, the antioxidant activity (DPPH and FRAP) and degree of inhibition of elastase participating in the proliferation processes of skin fibroblasts were determined in an in vitro model. The extracts and fractions were analyzed using high-performance liquid chromatography-photodiode array detection (HPLC-PDA) to quantitatively characterize their main polyphenolic compounds. The high antioxidant activity of the JM4-JM5 fractions correlated with the content of luteolin and its derivative 7-O-glucoside. Luteolin also showed the highest anti-elastase activity with an IC50 value of 39.93 ± 1.06 μg/mL, and its substantial content in the JM4 fraction presumably determines its activity (359.03 ± 1.65 μg/mL). At lower concentrations (<50 μg/mL) of all extracts, cell proliferation and migration were significantly stimulated after 24 h of treatment. The stimulation of cell migration was comparable with that of allantoin, which was used as a positive control. However, most of the tested extracts showed limited capacity to affect collagen type I biosynthesis. Moreover, the tested samples exhibited a complex effect on cytokine secretion, and the strongest anti-inflammatory activity through the moderation of IL-1β, IL-6 and IL-8 was observed for JM4 and luteolin. Based on the obtained results of the quantitative analysis, the anti-inflammatory activity of JM4 may be due to the high content of luteolin. In summary, extracts from J. montana, which is flavonoid-rich, promote the viability and accelerate the migration of fibroblasts as well as moderate oxidant and inflammatory processes and elastase activity. Hence, they may be potentially useful for topical therapeutic applications to stimulate the wound healing process.

Chronic Inflammation in Non-Healing Skin Wounds and Promising Natural Bioactive Compounds Treatment

Chronic inflammation is one of the hallmarks of chronic wounds and is tightly coupled to immune regulation. The dysregulation of the immune system leads to continuing inflammation and impaired wound healing and, subsequently, to chronic skin wounds. In this review, we discuss the role of the immune system, the involvement of inflammatory mediators and reactive oxygen species, the complication of bacterial infections in chronic wound healing, and the still-underexplored potential of natural bioactive compounds in wound treatment. We focus on natural compounds with antioxidant, anti-inflammatory, and antibacterial activities and their mechanisms of action, as well as on recent wound treatments and therapeutic advancements capitalizing on nanotechnology or new biomaterial platforms.

Wound Healing Activity of Nanoemulgel Containing Artocarpus lakoocha Roxb. Extract on Burns Model in Rat

BACKGROUND: The content of secondary metabolites in mobe leaves has the potential to be used in wound healing. Artocarpine, one of the secondary metabolites found in mobe leaves, is reported to affect the expression of transforming growth factor-beta (TGF-β) protein, thereby increasing fibroblast cell proliferation and accelerating the wound healing process. AIM: This study aims to determine the wound healing activity of nanoemulgel-containing ethanol extract of mobe leaves. MATERIALS AND METHODS: The method used in this study was experimental using chemicals ethanol 96%, Carbopol 940, PEG 400, Propylene glycol, Methyl Paraben, Propyl Paraben, Triethanolamine, Aqua Destillata. Mode leaves which were taken purposively were then formulated in nanoemulgel preparations which were tested for wound healing in male rats. The nanoemulgel preparation was then evaluated which included homogeneity, emulsion type, pH, viscosity, dispersion, and measurement of the nanoemulgel globules of mobe leaf extract, stability of the nanoemulgel preparation. Tests for the healing effect of burns were carried out on male rats for 14 days. RESULTS: Mobe leaves ethanol extract can be formulated into nanoemulgel dosage forms. This study showed wound healing activity of nanoemulgels with concentration variation of mobe leaves ethanol extract. The percentage of wound diameter reducing and fibroblast cells value were showed to increase and significantly different to negative control (p < 0.05) in 14 days. Platelet-derived growth factor (PDGF)-BB and TGF-β1 immunoexpression evaluation result showed significantly different to Blanko group (p < 0.05) in 14-day observation. CONCLUSION: From this study, nanoemulgel mobe can stimulate more fibroblast cell proliferation by greatly expressing TGF-β1 and PDGF BB in burn wounds.

Evaluation of Wound Healing and Antibacterial Potential of Greyia radlkoferi Szyszyl. Ethanolic Leaf Extract

Angiogenesis is an essential mechanism in both physiological and pathological functions, such as wound healing and cancer metastasis. Several growth factors mediate angiogenesis, including vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF). This study evaluated the potential wound healing activity of Greyia radlkoferi Szyszyl (GR) and its effect on growth factors regulating angiogenesis. The ethanolic leaf extract of GR was evaluated for antibacterial activity against wound associated bacteria; Staphylococcus aureus and Pseudomonas aeruginosa. It exhibited antibacterial activity against two strains of S. aureus (ATCC 25293 and ATCC 6538) displaying a minimum inhibitory concentration (MIC) at 250 and 500 μg/ml, respectively. The antioxidant activity of the extract was investigated for nitric oxide (NO) scavenging activity and showed a fifty percent inhibitory concentration (IC₅₀) of 1266.5 ± 243.95 μg/ml. The extract was further investigated to determine its effect on the proliferation and modulation of growth factors secreted by human keratinocytes (HaCaT). Its effect on wound closure was evaluated using the scratch assay, where non-toxic concentrations were tested, as determined by the antiproliferative assay against HaCat cells (IC₅₀ > 400 μg/ml). Results showed that the extract significantly inhibited wound closure, with a percentage closure of 60.15 ± 1.41% (p < 0.05) and 49.52 ± 1.43% (p < 0.01) at a concentration of 50 and 100 μg/ml, respectively, when compared to the 0.25% Dimethyl sulfoxide vehicle control (65.86 ± 1.12%). Quantification of secreted growth factors from cell-free supernatant, collected from the scratch assay, revealed that the extract significantly decreased the concentration of platelet-derived growth factor (PDGF-AA) at both 50 (p < 0.05) and 100 μg/ml (p < 0.001) (443.08 ± 77.36 and 178.98 ± 36.60 pg/ml) when compared to the 0.25% DMSO vehicle control (538.33 ± 12.64 pg/ml). Therefore, whilst the extract showed antibacterial activity against wound associated bacteria, it did not induce wound healing but rather showed a significant inhibition of wound closure, which was confirmed by the inhibition of PDGF-AA, a major growth factor involved in angiogenesis. Therefore, the GR extract, should be considered for further investigation of anti-angiogenic and anti-metastatic properties against cancer cells.

Flavonoids Inhibit Cancer by Regulating the Competing Endogenous RNA Network

Flavonoids are present in a wide range of plants. They have been used in the treatment of cancer, but the mechanism underlying this activity is unclear. In recent years, microRNA (miRNA) and long non-coding RNA (lncRNA) levels have been observed to differ between normal tissues and cancer cells, and both types of RNA have been shown to have a role in tumor treatment. In addition, flavonoids have been proven to regulate miRNAs and LncRNAs in the treatment of cancer. The competing endogenous RNA (ceRNA) network is a complex post-transcriptional regulatory mechanism in cells, in which coding and non-coding RNAs competitively bind miRNAs to regulate messenger RNAs (mRNAs). This review focused on the role of the ceRNA network in the treatment of cancer by flavonoids.